Category Archives: seeds

More than 100 Seed Companies!

The following is a list of more than 100 seed companies, including seed potato and garlic. Many of them have free catalogs and/or informative websites. This is a great resource as you are planning your 2025 garden. If a company is missing, add it in the comment box. For a source of ornamental bulbs, see the “Bulb Companies” tab on pegplant.com

Seed Companies

3 Porch Farm https://3porchfarm.com/

Adaptive Seeds http://www.adaptiveseeds.com

Alliance of Native Seedkeepers https://www.allianceofnativeseedkeepers.com/

American Meadows  http://www.americanmeadows.com

Ardelia Farm (sweet peas) https://www.ardeliafarm.com/

Artisan Seeds https://store.growartisan.com/

A. Whaley Seeds https://awhaley.com/

Baker Creek Heirloom Seed http://www.rareseeds.com

Botanical Interests http://www.botanicalinterests.com

Burpee http://www.burpee.com

Companion Plants https://companionplants.com/

The Cucumber Shop (yes, all things cucumber) https://cucumbershop.com/

Earl May https://www.earlmay.com/

Eden Brothers http://www.edenbrothers.com

Ernst Seeds https://www.ernstseed.com/

Everwilde Farms https://www.everwilde.com/

Experimental Farm Network https://www.experimentalfarmnetwork.org/

Fedco Seeds http://www.fedcoseeds.com

Ferry Morse https://ferrymorse.com/

Filaree Farm https://www.filareefarm.com/

Floret Flower Farm https://www.floretflowers.com/

The Good Seed Company https://goodseedco.net/

Grand Prismatic Seed https://www.grandprismaticseed.com/

Gurneys Seed and Nursery Company  http://www.gurneys.com

Harris Seeds http://www.harrisseeds.com

Harvesting History http://www.harvesting-history.com

Henry Field’s Seed and Nursery Company http://www.henryfields.com

High Country Gardens  http://www.highcountrygardens.com

High Desert Seeds http://www.highdesertseed.com/

High Mowing Seeds http://www.highmowingseeds.com

Hudson Valley Seed Library http://www.seedlibrary.org

Irish Eyes https://irisheyesgardenseeds.com/

Izel Native Plants https://www.izelplants.com/

J.L. Hudson, Seedsman https://www.jlhudsonseeds.net/

John Scheepers Kitchen Garden Seeds http://www.kitchengardenseeds.com

Johnny’s Selected Seeds http://www.johnnyseeds.com

Jordan Seeds https://jordanseeds.com/

J.W. Jung Seed http://www.jungseed.com

Kitazawa Seed Company http://www.kitazawaseed.com

Mary’s Heirloom Seeds http://www.marysheirloomseeds.com

MIgardener https://migardener.com/

Mountain Valley Growers https://www.mountainvalleygrowers.com/

Native Seeds Search http://www.nativeseeds.org

Nichols Garden Nursery http://www.nicholsgardennursery.com

Osborne Quality Seeds https://www.osborneseed.com/

Park Seed http://www.parkseed.com

Peace Seedlings http://peaceseedlingsseeds.blogspot.com/

Peaceful Valley Farm and Garden Supply http://www.groworganic.com

Pinetree Garden Seeds & Accessories http://www.superseeds.com

The Plant Good Seed Company https://www.plantgoodseed.com/

Prairie Road Organic Seed https://www.prairieroadorganic.co/

Prairie Moon Nursery https://www.prairiemoon.com/seeds/

Quail Seeds https://www.quailseeds.com/

Redwood Seeds https://www.redwoodseeds.net/

Renee’s Garden  http://www.reneesgarden.com

Renaissance Farms http://www.renaissancefarms.org

Restoration Seeds https://www.restorationseeds.com/

R.H. Shumway http://www.rhshumway.com

Richters (Canadian) https://www.richters.com/

Rohrer Seeds https://rohrerseeds.com/

Row 7 Seed Company https://www.row7seeds.com/

Salerno Seeds https://www.salernoseeds.com/

Sand Hill Preservation Center https://www.sandhillpreservation.com/

Sandia Seed Company https://www.sandiaseed.com/

SeedGro https://www.seedgro.com/

Seeds for Generations https://seedsforgenerations.com/

Seeds ‘n Such https://seedsnsuch.com/

Seeds of Change http://www.seedsofchange.com

Seed Savers Exchange http://www.seedsavers.org

Seeds from Italy http://www.growitalian.com

Seeds of India https://www.seedsofindia.com/

Seedwise https://www.seedwise.com/

Select Seeds/Antique Flowers http://www.selectseeds.com

Sierra Seeds https://sierraseeds.org/

Siskiyou Seeds https://www.siskiyouseeds.com/

Sistah Seeds https://www.sistahseeds.com/

Snake River Seed Cooperative https://www.snakeriverseeds.com/

Southern Exposure Seed Exchange http://www.southernexposure.com

Sow True Seeds https://sowtrueseed.com/

Stokes Seeds http://www.stokesseeds.com

Strictly Medicinal Seeds https://strictlymedicinalseeds.com/

Swallowtail Garden Seeds https://www.swallowtailgardenseeds.com/

Territorial Seed Company http://www.territorialseed.com

Terroir Seeds http://www.underwoodgardens.com

The Maine Potato Lady https://www.mainepotatolady.com/productcart/pc/home.asp

Thresh Seed Company https://www.threshseed.com/

Tomato Fest https://www.tomatofest.com/

Tomato Growers Supply Company http://www.tomatogrowers.com

Totally Tomatoes http://www.totallytomato.com

True Leaf Market https://www.trueleafmarket.com/

True Love Seeds https://trueloveseeds.com/

Turtle Tree Seed https://turtletreeseed.org/

Two Seeds in a Pod https://twoseedsinapod.com/

Ujamaa Seeds https://ujamaaseeds.com/

Underground Seed Company https://www.undergroundseedco.com/

Uprising Seeds https://uprisingorganics.com/

Urban Farmer http://www.ufseeds.com

Vermont Bean Seed Company http://www.vermontbean.com

Victory Seeds  http://www.victoryseeds.com

West Coast Seeds  https://www.westcoastseeds.com/

Wildflower Farm https://www.wildflowerfarm.com/storefront.html

Wild Garden Seed https://www.wildgardenseed.com/

Wild Mountain Seeds https://wildmountainseeds.com/

Wildseed Farms  https://www.wildseedfarms.com/

Willhite Seed Inc. https://www.willhiteseed.com/

Wood Prairie Farm https://www.woodprairie.com/

 

Winter Sowing Snapdragons

This year I am winter sowing snapdragons (Antirrhinum majus), which are annuals that prefer to bloom in the cool spring season. Easy to grow from seed, snapdragons have been bred extensively. There are cultivars with traditional “snap” flowers, open-faced flowers, or double flowers in all colors except for blue. There are dwarfs (6-15 inches), intermediate (15-30 inches), and tall snapdragons (30-48 inches) as well as trailing varieties. These plants are very versatile. They can be grown in rock gardens, containers, hanging baskets, or in the garden.

Snapdragons need full sun and moist but well drained soil high in organic matter. Although they are known for blooming in the spring, if kept watered in the summer and deadheaded, they could bloom again.

Madame Butterfly is an excellent cut flower type and a 1970 All-America Selections Flower Winner

I winter sow snapdragons for several reasons: 1) starting from seed provides a wider range of varieties; 2) starting from seed is cheaper; and 3) winter sowing gives me a jump on the spring season.

In early spring, I will open up the milk jug and transplant the seedlings into the garden. They can take a light frost.

Snapdragons make an excellent cut flower. They need to be deadheaded to encourage a long blooming period. The florets start opening at the bottom of the flower spike first so remove those spent flowers first. Or just cut the entire flower head when blooms are past their prime but cut at the base of the plant.

When cutting the flowers for the vase, cut when a few florets have opened at the bottom and the top buds are still closed. Cut the stem at the base, near the ground and strip off the lower leaves. Cut snapdragons last several weeks.

Try growing snapdragons in your garden this year for deer resistant, cool season flowers.

Snap Doubleshot Yellow Red Heart is a 2025 All-America Selections Ornamental Seed Winner

 

Bottom two photos are courtesy of All-America Selections.

Color Your Cocktail with Butterfly Pea

Often seen in cocktails on social media, butterfly pea plants (Clitoria ternatea) are vines that bloom beautiful pea-like flowers, about 2 inches wide. Typically, flowers are cobalt blue with a yellow inner strip. A member of the legume family (Fabaceae), the green leaves are similar to Kentucky coffee trees.

The flowers are also available in white,  lavender, and a pale light blue, single or double flower, but the cobalt blue is well-known in Asian countries. The flowers are dried and sold in bags, or in powdered form, or as an extract. A tea is made with the flowers, which can be brewed alone or with other herbs such as lemongrass, ginger, and mint.

When brewed with boiling water the tea is blue and can be drunk like an herbal tea. However, when an acid is added, such as lemon juice, the tea turns purple. When an alkaline liquid such as roselle tea is added, the tea turns red. Butterfly pea tea acts like a litmus strip, the color of the drink changes with the pH of what it is mixed with. This does not affect the taste but has transformed butterfly tea into a novelty cocktail drink. You will find lots of cocktail drinks made with the flowers on the internet. The blue flowers also are used to dye food such as custards, puddings, rice dishes, and sticky rice.

Butterfly pea is native to Africa. Here in Virginia it is grown as an annual which grows rapidly in the summer up a trellis or obelisk. As a member of the pea family, the plant fixates nitrogen, which is good for the soil. The vine can take full sun to light shade and is drought tolerant.

I have not seen the plant sold at local garden centers but you can order seeds online. It is relatively easy to grow from seed and once you have a mature plant, you can let some flowers go to seed to save the seed pods. Save the pods and split open when dried to reveal the seeds. Save the seeds to grow next year.

Here are a few online seed companies: Eden Brothers, Baker Creek Heirloom Seeds,  Park Seed, Strictly Medicinal Seeds, and Hudson Valley Seed Company. Include the butterfly pea with your 2025 seed order and try growing magical flowers!

Winter Sowing 101

Now that December is here it is time to plan for winter sowing. Winter sowing is a method of starting seeds outside in plastic containers in the winter so the seeds will have germinated by spring. In the spring, you transplant the seedlings to your garden bed. There are many advantages to winter sowing your seeds. You can:

  • start seeds without indoor lights;
  • start plants from seeds which is more economical;
  • start plants from seeds so you can take advantage of a wider selection of plants;
  • provide stratification (a cold period) or scarification (breaking the hard seed coat) for seeds that need it in order to break dormancy; and
  • get a jump on the cool season plants so they are able to flower or thrive in the spring before the summer’s heat.

Winter sowing is ideal for perennials, hardy annuals, semi or half-hardy annuals, and the cool season greens, veggies and herbs. Hardy annuals can tolerate cold soil and weather down to the 30’s, such as light frost and moderate freezing. Most hardy annuals expire in the beginning of the summer – they do not like the heat. Examples of hardy annuals are calendula, cornflower, annual larkspur, and pansies. Semi or half-hardy annuals can tolerate cool temperatures and cool soil down to the 40’s; they are damaged by frost. They too do not like the summer’s heat. Examples are baby’s breath, bells of Ireland, blue sage, forget-me-knots, and strawflower.

Cool season veggies, greens, and herbs include lettuce, peas, beets, radishes, broccoli, spinach, parsley, cilantro, and chervil.  Usually, one does not winter sow the warm season veggies such as tomatoes and peppers.

Seed packets and catalogs will not mention winter sowing but if you read the descriptions, you will see clues as to what plant would benefit from winter sowing. Look for words such as:

  • Hardy
  • Withstands frost
  • Self-sowing
  • Colonizing
  • Stratification required (cold period)
  • Scarification required (nicking or soaking in water)
  • Direct sow in early spring/late fall
  • Sow as early as the ground can be worked

In the DC metro area, we start winter sowing on or after the winter solstice which is December 21 and any time through January. There is no need to count days or weeks from average last frost date like you would if you were to start annuals under lights indoors.

To start winter sowing, look for plastic containers that can hold 3 to 4 inches of soil with about 2 to 3 inches headroom for the seedlings. You will often see gallon milk jugs but there are other options:

  • Clear, not opaque gallon milk, water, iced tea, juice, or apple cider jugs
  • Large plastic container of pretzels or Twizzlers that come in bulk size for the office
  • Coffee cans (cover with plastic)
  • Plastic container used to sell a roasted chicken (has a high dome)
  • 2-liter plastic soda bottles
  • Large plastic ice cream containers

Assuming you are using a gallon milk jug, make sure it is clean first and throw away the cap (do not need to cover the top).

Create several drainage holes in the bottom with a knife, exacto knife, box cutter, electric drill, or a hot glue gun without the glue.

Using a blade or scissors, cut around and below the handle or about 4 inches from bottom. Do not cut all the way across; leave a hinge on the handle side.

Fill the jug with 3-4 inches of potting mix. Do not use seed starting mix. Do not use soil from the ground or compost pile and do not use bagged soil with “moisture control” or water storing crystals. PRO-MIX works well.

Water the soil so it is moist. Sow seeds of one variety per container. If they are very fine seeds, press down so is in contact with moist soil. If very large, like coriander, press down, cover with a thin layer of soil. Water again and make sure seed is in contact with moist soil.

Close up the jug with duct tape and label or mark it some way so you remember what you sowed. Sharpies will fade so try grease pencils, colored nail polish/paint, or different colored ribbons. I used old lanyards from conferences and old colored pipe cleaners from craft projects, tied around the handles. I then wrote down which one signified which seed. Always keep a record of what you have sowed and when on paper or on your computer.

Place the jugs outside in full sun where they can collect rain or snow. It is not necessary for it to snow in your area for this to work. Periodically check to make sure they are okay — dogs or foxes did not tip them over. You will have to make sure they have enough moisture. If it has not rained or snowed, you may have to add water through the opening. If you lift the jugs and they feel light, they will need water. If on a warm day you do not see any condensation in the jugs, you may want to add more water.

In the spring, you should see seedlings. When they are a few inches tall, or when they have two sets of real leaves, open up the containers and let the seedlings sit in full sun for a few days.

Depending on the plant’s preference for cool weather and the size, you may want to move the seedlings to a larger container to let them continue to grow or you may want to transfer to the garden bed. Also depending on the seedlings, you can either pick out individual seedings or take a hunk or chunk (like carving brownies). It really depends on the size/width of individual seedlings (i.e., if thin and fragile may want to take a chunk but if the stems are stout and strong, you can transfer each one). Needless to say, it also depends on your patience.

I have friends who stay in Florida for the winter, so they set their jugs out after Christmas and then come back to seedlings, ready to be transplanted into the garden. It is that easy. Try winter sowing this year, you still have plenty of time to get your containers, soil, and seeds.

Saving Seeds from Your Garden

Blackberry lily seeds are easy to identify and save

As your plants flower and set seed and your fruit ripens on the vine, think of what you would like to save for next year. Saving seed can be easy and cost effective. In addition to saving seed to plant in your garden next year, you can give away seed packets as gifts or participate in seed swaps.

There are two methods for separating and cleaning the seed depending on the plant. Use the dry method for seeds that are in dried flowers, dried husks, or dried pods like beans, peas, grains, okra, marigolds, cone flowers, calendula, dianthus, basil, mustards, lettuce, kale, dill, fennel (any member of the carrot/dill family and the brassica/broccoli family). Use the wet method when the seeds are imbedded in the fleshy fruit, such as tomatoes, cucumbers, melons, squash, and eggplant.

Dry Method of Saving Seeds

Usually the plant has more than one flower head, each with their own timeline of flowering and setting seeds. During the summer, when the individual flower head has dried or when most of the seeds appear to be dried, cut the seed head and put in a paper bag. Cut when the stalks are brown at least an inch down from the seed head. Label the bag with the plant name and date. Continue to cut and save this way until you are ready to separate seed from fruit.

The flowers of nasturtiums drop off when past their prime and the seeds grow and become prominent later

Some flowers, such as nasturtiums and four o’ clocks, have a single flower that blooms and drops revealing a seemingly empty calyx. Soon though a seed will grow and become more prominent, making it easy to separate and save.

Beans and peas are fleshy so you can cut when the pod has become leathery or yellow and not completely dry. Let it continue to dry off the vine on a cookie sheet until the seeds rattle in the pods. For peppers, it is important to let the fruit ripen to the last color stage (many progress from green to red). For the cool season lovers such as greens (lettuce) and brassica family members such as kale, mustard, pak choi, cabbage, and broccoli, let the plant bolt (flower). Then cut and put in a bag.

Many seeds, especially beans, are also beautiful

In the winter, when I can’t go outside and garden, I gather all my bags and sit down at the dining room table. I put the seed heads on a white dinner plate or a cookie sheet to make it easier to see the seeds and prevent them from rolling off the table. By this time, the seeds and husks are completely dry and I simply pull apart the seed from the husk on the plate. If it is easy to remove, like marigolds, I put the seeds in a glass jar. If it is a fine seed with a lot of husks, like pak choi, I thrash it around in a large paper bag so that the seed falls to the bottom. I pull out and throw away the stems and pods and dump out the seeds on a cookie sheet. I separate further on the plate or I use a sieve. If the seed has a lot of chaff, I continue to separate seed by screening with a sieve. Eventually I work my way down from large grocery bags to small jars.

Wet Method of Saving Seeds

For this method the fruit has to be very ripe. For pumpkins, squash, and melon, simply remove the seeds and rinse the stringy fruit parts off with water, straining with a colander. For eggplant, cut into cubes and cover with water for a day, stirring once. Squish the seeds out and clean off with water in a colander. If there are remaining seeds, repeat the process the next day to get the rest out. Put clean seeds on a cookie sheet and let dry.

Pumpkin seeds can be saved or eaten

For cucumbers, scoop seeds out and put in a jar. Add water and stir every day for 2 days. Strain to remove seeds and let dry on a cookie sheet.

For tomatoes, squeeze or cut up the flesh and put into a jar. Add enough water to be able to stir the mixture and to create volume for the pulp to separate from the seeds. I keep my jars in the kitchen out of direct light and stir daily for a few days. The tomatoes will ferment and will look gross but this process separates the seeds.

After a few days, the heavy seeds will sink to the bottom and the lighter seeds and pulp will float to the top. Skim off and throw away the top layer. Keep the heavy seeds, they are the ones that are viable. Keep adding water, swishing until the good drops down and the bad surfaces, and skim again. Keep doing this until the water is clear with good seeds at the bottom. Pour the mixture into a sieve and put the seeds on a plate or cookie sheet in a dry area, out of direct light. Every few hours, stir around until dry. You want them to dry quickly at this point in time because the moisture left on them may induce them to germinate. Once they seem dry, let them sit for several weeks until completely dry and then store in a glass jar.

Open Pollinated versus Heirloom Plants

When saving seeds, it is important to know if your plants are open-pollinated or hybrids. If they are open pollinated, then the next generation will be the same. You will get the same plant with the same characteristics such as flower color or flavor. Heirlooms are open pollinated so you can save seeds of heirloom tomatoes and grow the same tomatoes each year.

If the plant is a hybrid, it was produced by crossing two genetically distinct parents. The hybrid was bred to have desirable characteristics such as disease resistance or better flavor. In seed catalogs, hybrids are often referred to as “F1”s – filial 1 hybrid. If you save the seed of this plant, the next generation may not retain the same desirable characteristics. You will get the same type of plant, but the plant may not be as tasty or not be resistant to a disease.

Try these simple methods to save seed for your own home garden or to give as gifts. Consider saving seeds for seed swaps with friends or local seed swap events.

Tips for Starting Seeds Indoors

marigoldsGardeners like to start seeds indoors to get a jump start on warm season plants such as tomatoes, peppers, and melons. They also start seeds indoors to be able to grow plants that have a longer growing season than the season in which they live. Before you begin to sow seeds indoors, read these sixteen seed starting tips to have as much success as possible. If you haven’t ordered your seeds yet, here is a list of seed companies.

ONE: The sunlight through your windows will not provide enough light. Use fluorescent tubes from hardware stores or purchase special grow lights but make sure their height can be adjusted. Seedlings are grown an inch away from the light source but as they grow the light source must be able to be adjusted. Lights have to be on for 14 to 16 hours daily but you can use a timer.

TWO: Yes, you can make your own seed starting mix but why? It is easier to purchase a bagged mix made especially for starting seeds – this mix is sterile with enough porosity for seeds to germinate and push through.

THREE: Not every seed should be started indoors. Some should be sown outdoors such as cilantro, dill, carrots, spinach, radishes, beans, and peas. Look at the seed package for instructions.

FOUR: What you use as a container is partially determined by what you are sowing. For example, if you are starting a lot of tomatoes, you can use one large tray because the seeds are likely to germinate and grow at the same rate. If you are sowing a variety of plants, use many small containers because each plant will have a different rate of germination and growth. Use plastic containers with drainage holes, draining excess water into a watertight, plastic tray. These can be small plastic cups, fruit cups, or yogurt cups. Another option is soil blocking.

FIVE: Once you sow and water seeds, you need to keep the seed moist until germination because if they dry out, they are no longer viable. This is why many people use clear plastic domes but remember to remove these domes when you see the seed emerge.

SIX: Water the mix in the container so it is moist before planting the seed. It will likely be hard to get moist, it may take several waterings, letting the water drain through, and tamping down with your fingers until you can sow the seeds. Then water again to soak the seeds.

SEVEN: The most common problem is “damping-off” which is caused by a fungus that thrives in warm, moist environments that are poorly ventilated. You will see pinched stems and seedlings that fall over. There is no recovering from this so one must prevent damping off by using clean containers, fresh water, increased air circulation, and not overwater.

seed packetsEIGHT: Usually, fine seed need light to germinate while larger seeds should be buried; check the seed package.

NINE: Heat mats are only necessary if you are starting warm season seeds in a cold area. Not all plants need this and not all places in the home need extra warmth. If you are starting seeds in a very warm room in the house (maybe upstairs – heat rises) you should be fine. If you are using a cool basement, you may need a seed heating mat. However, once the seeds have emerged, they can tolerate cooler temperatures.

TEN: Always label and keep records–within weeks you won’t remember anything. Because the small containers will be close together and under the light, you may want to mark the containers with a black magic marker instead of using plant tags at first.

ELEVEN: What you will see first is not the true leaves but the cotyledons. These once were the halves of the seed. They will look like leaves but soon they will shrivel and die off. Then you should see the first set of true leaves that can begin the photosynthesis process (i.e., make its own food). Decrease watering as you see growth emerge because really the roots are now down deep in the container taking up water so the surface can look a little drier than when you first sowed.

TWELVE: If you planted too many in one container, you can transplant seedlings into other containers after you see this first set of true leaves. Alternatively, you can remove the weakest looking ones with small scissors, just cut across at the base of the soil, do not pull it out.

THIRTEEN: When to start the seed indoors under lights? First determine your average last frost date for your area. Then count backwards the number of weeks given on the seed package. For example, if I use Mother’s Day as my average last frost date then I would start Black Krim tomato seed 6 weeks prior so it would be the last week in March. In that six-week timeframe, I know that probably the last 2 weeks, end of April, beginning of May, I will have moved the seedling to a larger 4-inch pot and place outside on the deck. This period will allow it to harden off.

FOURTEEN: Some seeds have to go through a scarification process where the seed coat either has to be nicked with a file or the seeds have to soak in a container of water for 24 hours before they are sown. For example, soak morning glories in water overnight before you sow them to help the process of breaking down the seed coat and letting the water in. Other seeds need to go through a stratification process of moist, cool temperatures several months before they will germinate. These seeds can be stored in the fridge for a few months before you attempt to sow them. Seed packets should state these requirements.

FIFTEEN: The caveat to #14 is that the seed packet is small and can only offer so much information, so read more information on the company’s website or catalog, or search on the internet, or look in a gardening book in order to have as much knowledge and success as possible for that particular plant.

SIXTEEN: Often there is too much seed in a packet. Don’t think you have to sow all the seed in the packet. In fact, save some in case your initial planting does not work out, or share/swap with friends, or use next year. Most vegetable seed will be viable next year with the exception of onions and leeks.

Good luck!

When Can I Plant My Tomatoes? Calculating the Last Spring Frost

Basil plants for sale in March in Northern Virginia

A lot of us are just itching to start seeds, purchase plants, and start gardening as soon as possible. It is important to know that some plants need warm summer weather, while others thrive in cool spring temperatures. Also, just because it is for sale does not mean that you should sow the seed now or plant the plant in your garden.

First, learn which of your plants/seeds are cool season versus warm season plants. Second, identify your average last frost date so you can figure out your starting time.

Cool season plants thrive in March and April. They can tolerate a cold nip at night. By summer, they may have disappeared, gone to flower, or died back. In the DC metro area, March and April are cool season months and this is when we can plant/sow seeds of spinach, lettuce, cilantro, and kale outside. However, if we were to plant a warm season plant such as tomatoes and basil outside, they would not survive a frost. Warm season plants have to be planted after the danger of frost has passed and the night temperatures are constantly in the mid-fifties. Usually they will do well in the summer, from May until our first autumn frost. You can start the seeds of basil and tomatoes indoors in April under lights where they will stay warm and toasty until you bring them out when it is warmer.

From winter to spring, the chance of frost diminishes. Although some gardeners will plant their warm season plants in mid April, there is still a slight risk of a frost. There is no risk in May and some gardeners use Mother’s Day as a marker for when they can safely plant warm season plants in the garden.

Tomato plants for sale in March in Northern Virginia

Many hardware stores and garden centers will sell plants as early as March, including basil and tomatoes.  People assume that because the plant is there for sale it is okay to plant it in the ground.

Frost is predicted when air temperatures reach 32 degrees. It also may occur when air temperatures are just above freezing due to open exposure to the clear night sky. Frost can be a “light freeze” at 29 to 32 degrees, which usually kills tender plants. Using the 1991-2020 climate normals from the National Oceanic and Atmospheric Administration, the National Gardening Association provides a useful chart outlining probabilities of cold temperatures by dates.

By entering my Northern Virginia zip code, I can see that March 29 is the point where there is a fifty-fifty chance of frost occurring. Some gardeners look for this point to get a head start knowing they may have to cover their plants.  I am more interested in being safe than sorry  — I have no desire to rush out and cover my plants so I am looking for a number lower than 50. Also, the National Gardening Association recommends using 36 degrees as the marker because frost can form at 32 degrees and then fall down into your garden even though it is 36 degrees on the ground. Using this logic, the 50/50 mark is April 9.

On April 10, I have a 10 percent chance of 32 degree temperatures. Ten days later, I have a 10 percent chance of 36 degree temperatures. As time goes by it, the 10 percent chance of frost will diminish to zero (until autumn). Because I am a low risk taker (or possibly too lazy to go outside and cover my plants), I am shooting for less than 10 percent to near zero. Therefore, I can plant basil and tomatoes at the end of April with a slight risk of frost to Mother’s Day when there is no risk.

At this point, when to plant is a personal preference and it also depends on your schedule, your available time. But don’t sow your tomato seeds now and do not plant tomatoes in the garden in March!

Lettuce: A Spring Crop for Containers or the Garden Bed

Soon we will be able to grow lettuce so order your seeds now. Lettuce prefers cool temperatures and can tolerate frosty evenings. This green is easy to start from seed or you can purchase small plants at the nursery.

Growing lettuce can be done in containers or in garden beds. Look for places that are full sun, especially where trees have not leafed out yet. Containers do not have to be large or deep. You can grow lettuce in containers with a depth as shallow as 6 to 8 inches.

In my Virginia garden, I  sow seeds in containers and the garden bed at the end of March and again every 2 weeks thereafter until the end of May. Lettuce seeds are very small so just press them into wet soil. Afterwards, make sure the soil does not dry out, which may mean watering often, depending on the weather. The squirrels like to dig in my containers on the deck so I apply a dust of blood meal. In the garden bed, I deter slugs with broken eggshells or Sluggo.

smart pot

Lettuce in a large fabric container

I tend to be heavy handed when I sow seeds. As the seedlings emerge, I have to remove some to create more space for the remaining plants. The thinnings can be used in a salad or transplanted to other areas of the garden. The nice thing about lettuce is that you can grow them before the tomatoes, peppers, and eggplants so you don’t need more land; you just double up on your existing land.

pepper with lettuce

Lettuce around a small pepper plant

I prefer the loose-leaf and romaine varieties. Loose-leaf, or cut and come again, has leaves that are loosely splayed outwards from the crown. They are the easiest to grow, quickest to harvest, and come in a variety of colors.  The entire plant can be cut at the base but most people cut the outer leaves as needed so the younger, inner leaves can take their place. Within this group are some of the best heat tolerant varieties. Romaine, also called cos, is not as sweet to me but I find that homegrown romaine is much tastier than store bought. Its stiff, vertical leaves are great for sandwiches and wraps. Romaine has the highest nutritional value of all the lettuces.

Flashy Trout Back lettuce

There are two other types that I have not grown: butterhead and crisphead. Butterhead, such as Bibb and Boston, has small heads of dark green leaves. These plants are so tight they have to be cut at the base and harvested whole. Crisphead is the familiar Iceberg, a tight ball of light colored leaves that requires a longer cool season than what we have in Virginia.

Try growing lettuce, you would be amazed at how it is easy and tasty! For a wider selection, order seed from companies because the nurseries have a limited selection. Here is a list of seed sources.

Seed Swaps: Fun Way to Get New Seeds!

It is that time of year again — seed swaps! National Seed Swap Day is Saturday, January 27, 2024, the last Saturday in January. Seed swaps are a great way to obtain new seeds, share your favorite seeds, and attend a fun event. A seed swap can be as simple as friends getting together to share seeds they saved from the previous gardening season to an all-day planned event with speakers, door prizes, and refreshments.

Seed swaps can be a vehicle to teach others how to save seed, the importance of seed diversity, heirloom seeds, and other aspects of gardening. Some exchange more than seeds; tables may be set up to collect used gardening books, magazines, tools, pots, and nursery catalogs. Some may expand their definition of seeds and allow bulbs, rhizomes, and cuttings. Others include related activities such as learning to make handmade seed envelopes.

Each seed swap is different but usually organizers have established guidelines for the seed such as the type of container to use, the number of seed in each bag, and the information required on the label. Organizers should clarify if commercial seed packages or hybrid seeds are accepted. Although swaps do not want seeds from invasive plants, the organizers should clarify the definition of an invasive plant in their area.

If you are interested in attending a seed swap, ask your local county extension agent or Master Gardeners if they know of seed swaps in your area. Check out my monthly list of local gardening events for seed swaps in the Washington DC metro area.

If you are interested in starting a seed swap, visit a few first to see the range of activities that could take place and the number of volunteers required. Read Seedswap: The Gardener’s Guide to Saving and Swapping Seeds by Josie Jeffery and download the Seed Savers Exchange’s 8-page handout on how to organize a seed swap. Happy #seedswapday!

More Than 100 Seed Companies!

The following is a list of more than 100 seed companies, including seed potato and garlic bulbs. If I missed one, please add it in the comments section. For a source of ornamental bulbs, see the “Bulb Companies” tab on pegplant.com. 

Seed Companies

3 Porch Farm https://3porchfarm.com/

Adaptive Seeds http://www.adaptiveseeds.com

Alliance of Native Seedkeepers https://www.allianceofnativeseedkeepers.com/

American Meadows  http://www.americanmeadows.com

Annie’s Heirloom Seeds http://www.anniesheirloomseeds.com

Ardelia Farm (sweet peas) https://www.ardeliafarm.com/

Artisan Seeds https://store.growartisan.com/

A. Whaley Seeds https://awhaley.com/

Baker Creek Heirloom Seed http://www.rareseeds.com

Botanical Interests http://www.botanicalinterests.com

Burpee http://www.burpee.com

Companion Plants https://companionplants.com/

The Cucumber Shop (yes, all things cucumber) https://cucumbershop.com/

Earl May https://www.earlmay.com/

Eden Brothers http://www.edenbrothers.com

Ernst Seeds https://www.ernstseed.com/

Everwilde Farms https://www.everwilde.com/

Experimental Farm Network https://www.experimentalfarmnetwork.org/

Fedco Seeds http://www.fedcoseeds.com

Ferry Morse https://ferrymorse.com/

Filaree Farm https://www.filareefarm.com/

Floret Flower Farm https://www.floretflowers.com/

Fruition Seeds https://www.fruitionseeds.com/

Gardeners Basics https://www.gardenersbasics.com/

The Good Seed Company https://goodseedco.net/

Grand Prismatic Seed https://www.grandprismaticseed.com/

Gurneys Seed and Nursery Company  http://www.gurneys.com

Harris Seeds http://www.harrisseeds.com

Harvesting History http://www.harvesting-history.com

Henry Field’s Seed and Nursery Company http://www.henryfields.com

High Country Gardens  http://www.highcountrygardens.com

High Desert Seeds http://www.highdesertseed.com/

High Mowing Seeds http://www.highmowingseeds.com

Hudson Valley Seed Library http://www.seedlibrary.org

Irish Eyes https://irisheyesgardenseeds.com/

Izel Native Plants https://www.izelplants.com/

J.L. Hudson, Seedsman https://www.jlhudsonseeds.net/

John Scheepers Kitchen Garden Seeds http://www.kitchengardenseeds.com

Johnny’s Selected Seeds http://www.johnnyseeds.com

Jordan Seeds https://jordanseeds.com/

J.W. Jung Seed http://www.jungseed.com

Kitazawa Seed Company http://www.kitazawaseed.com

Lake Valley Seed https://lakevalleyseed.com/

Mary’s Heirloom Seeds http://www.marysheirloomseeds.com

MIgardener https://migardener.com/

Mountain Valley Growers https://www.mountainvalleygrowers.com/

Native Seeds Search http://www.nativeseeds.org

Nichols Garden Nursery http://www.nicholsgardennursery.com

Osborne Quality Seeds https://www.osborneseed.com/

Park Seed http://www.parkseed.com

Peace Seedlings http://peaceseedlingsseeds.blogspot.com/

Peaceful Valley Farm and Garden Supply http://www.groworganic.com

Pinetree Garden Seeds & Accessories http://www.superseeds.com

The Plant Good Seed Company https://www.plantgoodseed.com/

Prairie Road Organic Seed https://www.prairieroadorganic.co/

Prairie Moon Nursery https://www.prairiemoon.com/seeds/

Quail Seeds https://www.quailseeds.com/

Redwood Seeds https://www.redwoodseeds.net/

Renee’s Garden  http://www.reneesgarden.com

Renaissance Farms http://www.renaissancefarms.org

Restoration Seeds https://www.restorationseeds.com/

R.H. Shumway http://www.rhshumway.com

Richters (Canadian) https://www.richters.com/

Rohrer Seeds https://rohrerseeds.com/

Row 7 Seed Company https://www.row7seeds.com/

Salerno Seeds https://www.salernoseeds.com/

Sand Hill Preservation Center https://www.sandhillpreservation.com/

Sandia Seed Company https://www.sandiaseed.com/

SeedGro https://www.seedgro.com/

Seeds for Generations https://seedsforgenerations.com/

Seeds ‘n Such https://seedsnsuch.com/

Seeds of Change http://www.seedsofchange.com

Seed Savers Exchange http://www.seedsavers.org

Seeds from Italy http://www.growitalian.com

Seeds of India https://www.seedsofindia.com/

Seedwise https://www.seedwise.com/

Select Seeds/Antique Flowers http://www.selectseeds.com

Sierra Seeds https://sierraseeds.org/

Siskiyou Seeds https://www.siskiyouseeds.com/

Sistah Seeds https://www.sistahseeds.com/

Snake River Seed Cooperative https://www.snakeriverseeds.com/

Southern Exposure Seed Exchange http://www.southernexposure.com

Sow True Seeds https://sowtrueseed.com/

Stokes Seeds http://www.stokesseeds.com

Stover Seed https://www.stoverseed.com/

Strictly Medicinal Seeds https://strictlymedicinalseeds.com/

Swallowtail Garden Seeds https://www.swallowtailgardenseeds.com/

Territorial Seed Company http://www.territorialseed.com

Terroir Seeds http://www.underwoodgardens.com

The Maine Potato Lady https://www.mainepotatolady.com/productcart/pc/home.asp

Thresh Seed Company https://www.threshseed.com/

Tomato Fest https://www.tomatofest.com/

Tomato Growers Supply Company http://www.tomatogrowers.com

Totally Tomatoes http://www.totallytomato.com

True Leaf Market https://www.trueleafmarket.com/

True Love Seeds https://trueloveseeds.com/

Turtle Tree Seed https://turtletreeseed.org/

Two Seeds in a Pod https://twoseedsinapod.com/

Ujamaa Seeds https://ujamaaseeds.com/

Underground Seed Company https://www.undergroundseedco.com/

Uprising Seeds https://uprisingorganics.com/

Urban Farmer http://www.ufseeds.com

Vermont Bean Seed Company http://www.vermontbean.com

Victory Seeds  http://www.victoryseeds.com

West Coast Seeds  https://www.westcoastseeds.com/

Wildflower Farm https://www.wildflowerfarm.com/storefront.html

Wild Garden Seed https://www.wildgardenseed.com/

Wild Mountain Seeds https://wildmountainseeds.com/

Wildseed Farms  https://www.wildseedfarms.com/

Willhite Seed Inc. https://www.willhiteseed.com/

Wood Prairie Farm https://www.woodprairie.com/