Category Archives: seeds

General’s Choice of Trees and Shrubs is a Wise Choice for the Mid-Atlantic Gardener

 

Spring is the season for plant sales in the Washington DC area. Every weekend there are plant and garden sales, garden parties, workshops, tours, and lectures. I look forward to these annual events just as much as I look forward to seeing the cherry blossoms. One of the more interesting plant sales is Mount Vernon’s Historic Plant and Garden Sale in Virginia. This year, the month-long sale runs from Saturday April 21 to May 20, 10:00 am to 6:00 pm (members can attend the preview night on April 20). The plants are located outdoors, just outside the Mt. Vernon main gift shop, and admission tickets are not necessary. Gardening accoutrements such as tools, books, mugs, note cards, and gift items also are available. Staff horticulturists, easy to spot by their bright green shirts, are available to answer gardening questions on Wednesdays and Sundays from 1:00 to 2:00 pm.

“At length my dear Marquis I am become a private citizen on the banks of the Potomac, & under the shadow of my own Vine & my own Fig-tree.”

What sets this plant sale apart from other local sales is provenance. The Mt. Vernon horticulturists propagated most of the plants that are for sale from the plants that are grown on the George Washington’s estate. There is a wide assortment of vegetables, flowers, herbs, trees, and shrubs. Of note is the General’s Choice Collection. Staff grew ten trees and shrubs representative of those that were grown by George Washington: three types of boxwood (American, English, and tree), two edibles (pawpaw and fig), tulip poplar, southern magnolia, redbud, dogwood, and red maple. The General’s Choice Collection has distinctive tags and can be grown easily by gardeners and homeowners in the mid-Atlantic area.

In addition, the Mt. Vernon horticulturists collected, cleaned, and packaged heirloom seed from plants grown on the estate. The beautifully designed seed packets make great souvenir gifts, easy to mail. The proceeds from the plant sale support the historical museum and gardens. Every time someone purchases a plant or a seed packet, George Washington’s legacy as a gentleman farmer lives on.

“Planted all my Cedars, all my Pawpaw, and two Honey locust Trees in my Shrubberies and two of the latter in my groves – one at each ‘side’ of the House and a large Holly tree on the Point going to the Sein landing.”

Photos courtesy of George Washington’s Mt. Vernon

Tips for Starting Seeds in Your Garden: Planting in the Spring

lettuce in container

Recently, I posted an article called Tips for Starting Seeds for Your Garden. The post was about starting seeds and the importance of distinguishing between warm versus cool season plants or seed. It further explained how and when to sow seeds for warm season plants. This is the second part of the post: a focus on cool season plants.

Starting Seeds in Ground or Containers

In my zone 7 Northern Virginia garden, there are many vegetable and herbs that I can start growing outside in early spring. This means I don’t have to start them indoors under lights. Not only do these particular plants prefer cool temperatures, a light frost should not harm them. I tend to start most of my cool season plants by seed in containers on my deck. Container soil is warmer than ground soil. Also, it is easier to check on them by walking on a wooden deck than to have to trample through wet, soggy soil in cold weather. By summer, most of these types of plants have bolted (i.e., flowered and gone to seed so leaves are bitter). After pulling and discarding into the compost pile, I re-stock my containers with warm season annuals such as different types of basils and bush beans.

When to Sow Seeds in Early Spring

Using davesgarden.com and my zip code, I calculated my average last frost date to be April 30. March and April are still cool and there is a possibility of a frost or even snow. From the list of cool season plants or seeds I want to grow, I calculate which I can start at what number of weeks before April 30 and which would benefit from containers on the deck or directly into the soil. If a seed packet does not provide this information, try asking your local extension agent, online seed catalogs, or read a printed seed catalog or a gardening book. A few online seed catalogs that provide quality descriptions for this are Burpee, Johnny’s Selected Seeds, Botanical Interest, Southern Exposure Seed Exchange, and Renee’s Garden.

chervil

chervil is a spring herb

Sowing Often for Continuous Harvest

For some cool season crops, sowing every couple of weeks ensures a continuous harvest until summer. For example, our family likes to eat lettuce and spinach so if I start sowing in early spring and again every other week, I will be able to continue to pick leaves for a family of four up until summer. By summer, the weather will be too hot to germinate spinach and lettuce easily.

spinach seedlings

direct sow spinach seedlings in container

Check if the seed package recommends growing in soil or if they can be grown in a container. If you only need a little arugula, grow in a shallow container. If you only need one borage plant, grow in a larger container (it is a larger plant). Chervil is so ephemeral it is best to grow in a medium container so you can access and harvest as much as possible. For plants that tend to flower and drop seed, I find it helpful to have a patch set aside. I have parsley, cilantro, and calendula patches in the backyard so I sow the seeds directly in those patches. Of the plants below, peas are the only ones that need vertical structure. They should be planted next to a trellis and “trained” to wrap around it. I grow sugar snap peas in the ground next to a wire trellis but there are some variety of peas that can be grown in containers with stakes. Here are common cool season plants that can be grown by seed:

  • Alyssum
  • Arugula
  • Asian greens
  • Beets
  • Borage
  • Calendula
  • Carrots
  • Chervil
  • Chinese cabbage
  • Cilantro
  • Dill
  • Endive
  • Greens
  • Kale
  • Kohlrabi
  • Lettuce
  • Mache
  • Mustards
  • Nigella
  • Pak choi
  • Parsley
  • Peas
  • Radish
  • Spinach
  • Sweet peas
  • Turnips

My Cool Season Seed Plan

Just before March 15

Burpee and Botanical Interests Sugar Snap Peas: Soak overnight in water and then plant seed in small plastic pots with soil. When 2 inches tall, transplant outside in ground against trellis. No need for indoor lights.

March 15

April 1

  • American Meadows Scarlet Nantes carrot, sow in large deep container on deck and in ground
  • Renee’s Garden Slo-Bolt Cilantro, sow directly into cilantro patch in ground

April 15

  • Repeat lettuce, seed, radishes, and kale
  • Start borage in large decorative container
  • Start arugula in medium container
pak choi

direct sow pak choi seeds in ground

 

Tips for Starting Seeds for Your Garden

melons

Tuscan melons get a head start when start seed indoors

Starting seeds now for the garden is tempting. Racks of seed packets with their pretty images of fresh vegetables and cut flowers are like heart-shaped boxes of chocolate. Each packet is a morsel, a promise of something good to come. Starting seeds is like eating chocolate, who can resist?

As with chocolate, however, some restraint is needed. February feels like it is time to sow seeds. Surely a garden center full of seed packets is sending us a message. But before you start, here are a few tips on when to start which particular plant. This is a two-part article: this article will explain the difference between cool and warm season plants and when to start warm season plants. The subsequent article will cover cool season plants.

Learn which plants prefer warm versus cool weather

The first step is to make a list of what you want to grow and/or your seed packets. From that list, identify which plants prefer cool or warm temperatures.

For example, if you wish to start seeds of tomatoes and cilantro, mark tomatoes as a warm season plant. Plant tomatoes outside when there is no danger of frost. Cilantro prefers cool weather and can tolerate a light frost.

If you don’t know, ask your local extension agent, look online at seed catalogs, or read a printed seed catalog or a gardening book. A few online seed catalogs that provide quality descriptions for this are Burpee, Johnny’s Selected Seed, Botanical Interests, Southern Exposure Seed Exchange, and Renee’s Garden. Just type in the plant name in their search bar and don’t worry so much about the cultivar for now.

tomato

Tomato transplants in an Earthbox in May

Learn your average last frost date

Focusing on the warm season plants for now, identify your average last frost date. Using davesgarden.com and my zip code, my risk of frost in my Northern Virginia zone 7 garden, is from October 13 through April 23. I am almost guaranteed not to get frost from May 9 through September 29. I arbitrarily picked April 30 as the day when I can move my transplants from inside to outside to harden off. Picking the end of a month makes it easy to remember and to calculate weeks.

Using April 30 as the marker, count back the number of weeks it takes for that seed to germinate and reach transplanting size. This information should be on the seed packet but if not go back to the original resources I listed above. My tomato seed packages say “start seeds 6 to 8 weeks before average last frost” or “before transplanting.” Keep in mind that this is only to get a jump on the season. You can always start seed outdoors after the danger of frost has past but quite a few weeks of growing season would be lost. Six weeks from April 30 is mid-March, which is when I would sow my tomato seeds in small containers under lights.

Purchase lights to starting warm weather seeds indoors

Starting seed by a window does not provide enough light. The seed container has to be just a few inches under the florescent tubes or special grow lights. Therefore if you are interested in growing from seed, invest in lights but you can use cheap fluorescent tubes from hardware stores. Once you turn on the lights, you keep them on for 14 to 16 hours every day until you move the plants outside.

Decide which seeds to start under lights

Your indoor light system becomes prime real estate. Within the category of warm season plants, identify which seeds should be started indoors in this prime real estate section, i.e., need a head start before the end of April. Separate that list from those that could be started outdoors in the beginning of May. For example, because beans germinate and grow quickly to produce a harvest, start them outdoors in May and save the prime real estate for tomatoes that need a month and a half head start. Identify the number of weeks recommended for starting seeds indoors for each plant. Usually one starts tomatoes, peppers, eggplants, broccoli, cabbage, cauliflower, collards, onions, celery, and Brussels sprouts indoors to get a jump on the season. Start beans, corn, watermelons, zinnias, sunflowers, summer squash, cucumbers, pumpkin, and basil outdoors in May.

roselle

Roselle is a tropical plant that needs a head start

This is an example of what my list looks like for starting seeds of warm season plants under lights. I will try several varieties of pepper, tomatoes, and melons, which takes up even more space under the lights.

March 1: Eight weeks prior to average last frost date of April 30

March 15: Six weeks prior to average last frost day of April 30

April 15: Two weeks prior to average last frost date of April 30

Time to Start Sowing Cool Season Flowers and Brassicas

mustard

This week on Facebook, Southern Exposure Seed Exchange, a Virginia-based seed company, reminded us to start cabbage, celery, celeriac, cauliflower, and bulb onions indoors (from seed, under lights). However, if you are worried about the dreaded cabbage worm and other pests, Margaret Roach in New York just interviewed Don Tipping from Siskiyou Seeds on her website, awaytogarden.com, for tips on growing brassicas and preventing the cabbage worm. Brassicas are members of the cabbage or mustard family (Brassicaceae) that include cauliflower, collards, broccoli, kohlrabi, kale, and the mustards, among others. Popular vegetables to grow here but they are susceptible to cabbage worm and flea beetle.

love in a mist seed pod

Claire Jones, Maryland garden/floral designer, tells us on her blog, The Garden Diaries, that now is the time to sow cool season flowers. She has sown seeds of calendula, love in a mist, poppies, and bells of Ireland outside, directly into the soil, when it was workable.

If you are new to the concept of cool season flowers, check out Lisa Ziegler’s website, The Gardener’s Workshop. She wrote the book (quite literally) because she has a cut flower farm in Newport News, Virginia. Her website has two virtual workshops (a series of short videos): one to learn how to start seeds indoors and one on growing cool season flowers. Last year, I was inspired and grew snapdragons, calendula, and love in a mist.

love in a mist flowers

snapdragons

Seed Swaps: Share Your Seeds and Try New Varieties

It’s that time of year again — seed swaps! National Seed Swap Day is this Saturday, January 27, 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 organizations 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 to allow bulbs, rhizomes, and cuttings. Others include related activities such as learning to make handmade seed envelopes.

seeds of blackberry lilies are easy to pick and save

Each swap is different but usually organizers have established guidelines. They may prescribe the preferred container, 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 no one want seeds from invasive plants, the organizers should clarify the definition of an invasive plant in that geographic 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 (three are listed below for this Saturday). Kathy Jentz, owner of the Washington Gardener Magazine, which hosts two events annually, keeps a running list of seed swaps across the country.

tiger beans are not only easy to save but beautiful

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 it would require. 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. Talk with other organizers to learn how to determine guidelines for accepting seed, the process to avoid a mad stampede to the seed table, and possible fun activities or speakers. Determine if you want a simple seed swap or a community event with speakers and an agenda. Now is the time to attend the seed swaps this year in order to plan your swap for next year.

The Washington Gardener Seed Exchange occurs every January-February with speakers and door prizes at Brookside Gardens, Wheaton, MD, and Green Spring Gardens, Alexandria, VA. This year, the Brookside Garden event will be on Saturday, January 27 and the Green Spring Garden event will be on Saturday, February 10. These are from 12:30 to 4:00 pm. There is a fee and registration is done via brownpapertickets.com. 

The Northern Shenandoah Valley Master Gardeners will host a seed exchange with vendors and book/magazine swap at the Blandy Experimental Farm Library, Blandy Farm, Boyce, VA;  January 27, 10:00 am to 2:00 pm, free.

The Central Rappahannock Extension Master Gardeners will host a seed swap, with speakers, door prizes, and refreshments at Central Rappahannock Regional Library, 1201 Caroline Street (theater), Fredericksburg, VA, on Saturday January 27, 10:00 am to 3:00 pm, free.

Seed Catalogs, Seed Catalogs, Get Your Seed Catalog!!

In anticipation of a great 2018 gardening season,  I have updated my list of seed catalogs on my website under the tab “seed catalogs” to include 38 companies. Note that many catalogs are free, just contact the company. I am starting to get seed catalogs in the mail but I usually wait until I have a quorum and then we sit down to chat. They say “buy me, buy me, I am new and better!” and I say “Yes, I want, I want, I want BUT do I have enough space? Do I have enough time?” And so it goes for weeks….

In a Vase on Monday: Marigolds for Autumn Color

Just good old fashioned marigolds but makes a great fall flower for the vase. Have been saving the seed each year and planting again until I forget where they originally came from. Easiest flower for saving seed. #inavaseonmonday

 

 

Growing Burpee’s Tomatoes and Heirloom Tomatoes this Summer

Labor Day Weekend Haul of Tomatoes

I have always grown tomatoes from seed, simply because I like to grow plants from seed. Tomatoes are particularly easy, they germinate fast and are easy to grow. Each year I start different tomato seeds indoors under lights and end up with many to give away. My family of four loves fresh tomatoes in the summer so I grow at least half a dozen tomato plants in our Virginia backyard.

This spring, a representative from Burpee Home Gardens asked if I would like to grow several tomato plants that Burpee was going to introduce in 2018. I was intrigued. Since I have not bought tomato plants in years, I thought it would be interesting to see the difference between these hybrids and my plants. Burpee has been selling seed for over 140 years but they also sell plants and they offer both heirlooms and hybrids for some of their vegetables.

I had already started the heirloom Marglobe (determinate slicer) from a source other than Burpee (Burpee also sells this) and Chianti Rose (indeterminate beefsteak) from seed when Burpee had contacted me. In May, I planted my seedlings and Burpee’s plants, each with a 6-foot tall post. Deer came through once or twice in early summer so I was left with the following from Burpee: two Gladiators (indeterminate paste), two Oh Happy Day (indeterminate junior beefsteak), and one Tomato Combo Take 2 Blockbuster (a determinate slicer and a cherry together). I also had two Marglobe and four Chianti Rose plants.

Heirloom Chianti Rose tomato

My two heirloom tomatoes are plants that have been grown from seed for generations. Heirlooms are usually passed down and have a story connected with them or are a family favorite. I could save the Marglobe or Chianti Rose seed, plant them next year, and get exactly the same type of plant. The Burpee plants are cultivars that have been bred to have particular characteristics. I could save the seed, plant them next year, and get tomatoes but they would not retain the same desired characteristics that Burpee had selected (usually disease resistance). Except for the annual deer visit, I don’t have a serious disease/pest problem in my garden with my plants.

Heirloom Marglobe, a determinate tomato plant

I do grow a combination of determinate and indeterminate tomato plants to space out my harvest. Indeterminate plants grow, bloom, and fruit over and over again until frost so you can harvest tomatoes throughout the summer. Determinate plants will stop growing when fruit sets on the top buds so the tomatoes ripen at the same time in a window of a few weeks.

As the summer progressed, I watered all the plants often with a hose, fertilized a few times, and strung the branches to the post with yarn (leftover from kids’ projects). This year, however, I felt that I had to keep stringing the tomatoes, more often than in the past. Every weekend I was stringing up the Gladiator and the Oh Happy Day plants to the stake and then having to string the branches up so they would not fall down. These two in particular were growing fast, with many branches and more weight. My yarn was becoming an aerial infrastructure just to keep branches up. My heirlooms were growing well but not as robust or as branched as these Burpee plants.

Burpee’s Gladiator paste tomato plant

In mid-August, I had harvested about 2 red tomatoes from the two Gladiator plants, which had about 10 green tomatoes on each plant. Gladiator is the first paste tomato plant that I have grown and it is firm enough for sandwiches and salads, not as wet and messy as the slicers or beefsteaks. Traditionally, paste tomatoes are used for pasta sauce and for dehydration so I plan to use these in our pasta sauce, chili, and bean stew. I would definitely use a cage next time; one stake is not enough. This particular type was bred to resist blossom end rot, which rarely occurs in my garden, but I did not see it on these plants.

Burpee’s Oh Happy Day with red tomato

The Oh Happy Day gave me a couple of red junior beefsteak tomatoes early in the season, which we used in salads and sandwiches. Anything that colors up early in the season is a plus in my book. In mid-August there were about 20 green tomatoes on each of the plants. This plant was very vigorous and again, I would use cages next time. The fruit clustered together, making it easy to simply twist a ripe one off the vine.

The Tomato Combo Take 2 Blockbuster is a combination of a small cherry tomato, a yellow indigo, and a determinate red slicer. Although I planted these in the ground, I would recommend planting in a large container on the deck. The plants are only a few feet tall and would make a great conversation piece on the deck or patio. It would also make it easier for people to see the pretty yellow indigo tomatoes. By mid-August, I harvested about 10 yellow indigos and a red slicer but there were about 5 green slicers and a few more yellow indigos on the plant.

Yellow Indigo cherry from Burpee’s Tomato Combo Take 2 Blockbuster plant

In mid-August, the Marglobe had a dozen green tomatoes on each plant. The plant seemed to be okay with the stake, it was not as heavily branched or as “viney” but then it is a determinate. Marglobe has very pretty fruit, red and round like a ball.

The Chianti Rose plants had about five green tomatoes on each plant. The Chianti Rose is not a pretty tomato, it is large and flattened, sort of an oblong beefsteak. It ripens to pink instead of red. Because the fruit is large, the plant bends under the weight. A cage would have been better, plus each plant took up a lot of space.

I have to confess I rarely have pests or diseases with my tomatoes so I did not notice any difference between Burpee’s plants and the heirlooms in this regard. I did notice that the Burpee plants had more vigor and growth so it would have been best to use cages for the Gladiator and the Oh Happy Day plants. They were large plants with many branches and more tomatoes than the Marglobe and Chianti Rose.  If I had to do it over again, I would have put the Tomato Combo Take 2 Blockbuster in a container. All of the tomatoes tasted good and it was great to learn that the paste tomatoes could be used for sandwiches and salads as well as pasta sauces. I am sure Burpee will have these plants for sale at the local garden centers next year.

Next year, grow tomatoes in the garden or in a container. Nothing beats their fresh taste — summer in a bite!

Oh Happy Day grows in clusters, easy to pick

Invasive Balloon Flower Takes Over the Garden

Today I tweeted that it would be good to pull weeds since it had rained buckets for the past few days, thus decreasing the heat and humidity and loosening the soil. For me, the time was ripe to pull an invasive plant from my garden, balloon flower (Platycodon grandiflorus). “Balloon flowers?” you say, “but it has such pretty blue flowers and the kids love to pop those inflated buds.” Yes, my kids did like to pop the buds on my original plants as they walked to the front door and yes, they do produce pretty blue flowers on tall stems all summer long. But after 10 years, the kids don’t see them anymore (because their heads are always bent down viewing their iPhones) and the original four have multiplied into hundreds, crowding out my other perennials in my Virginia garden.

original four plants have multiplied on left side of walkway and have tan seed pods (directly across walkway is one balloon flower from front garden bed)

Part of problem is that balloon flowers self-seed very fast. The plants could be deadheaded to prevent self-seeding but this is a nerve racking, time consuming task. Each single seed pod has to be clipped off in order to leave the remaining buds or open blossoms. It is not possible to whack the entire plants down a foot. And part of the problem is that they are deer-resistant, drought-resistant, and generally pest free but the worst part is that balloon flowers have long, large tap roots. Breaking off the stem just encourages more stems to grow from the root. Although it is easier to pull and dig after it rains, I still spent hours pulling and digging to get the whole roots out as much as I could. I suspect I did not dig deep enough though, there probably are pieces in the soil that will rise again like the phoenix.

seeds landed on front strip across walkway (blooming with blue flowers)

Interestingly, I have found little reference to its invasive attribute on the internet. I did learn that the Kitazawa Seed Company catalog sells them and according to their description, the root, called doraji, is used in Korean cuisine. It is also used as an anti-inflammatory to treat colds and is considered a cheap ginseng substitute. The root can be dried and packaged for sale in Asian markets.

Unless you want to grow your own doraji for medicinal or culinary reasons, don’t plant this invasive perennial in your garden no matter how much fun you have popping the balloons.

pulling to reveal tap root

 

New Videos on Plant Propagation From Virginia Cooperative Extension Master Gardener Program

The Virginia Cooperative Extension Master Gardener Program has produced a series of 10 short videos on YouTube about plant propagation. Filmed in the Virginia Tech greenhouses, each video is about 4 minutes or less. Topics include seeding, transplanting, grafting, air layering, tomato grafting, and the many different types of plant division. These will be helpful as you begin to start seeds indoors now or if you are interested in dividing and multiplying your houseplants.