Tag Archives: warm season

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

Get Your Seed Catalogs Now and Plan for Next Year!

Decemberseedcatalogs2014 001Over the Thanksgiving weekend I had the honor of being a guest on the Garden America radio show, formerly known as GardenLife. Garden America is a nationally syndicated, live talk show hosted by Sharon Asakawa, John Bagnasco, and Bryan Main. They are in San Diego but Sharon had read my blog and contacted me so we arranged for me to be called in on a Saturday morning. Sharon, John, Bryan and I talked about growing vegetables, seed catalogs, and lessons learned from my 2014 gardening season. One of the points I made was that many seed companies have produced their catalogs for the 2015 growing season and are either available now or will be in a few weeks. Most are free, full-color resources that describe common edibles and the requirements for growing them from seed. Among the catalogs, specific details such as average seed life, insect problems, and germination rates may or may not be mentioned so I suggested that people contact several companies and get a few catalogs to compare and contrast the descriptions.

lettuce

lettuce

Keep in mind that catalogs lists the plants in alphabetical order, but nature does not. The first lesson in edible gardening is to learn which plants prefer cool temperatures and which plants prefer warm temperatures. Re-arrange the plants in the catalogs by cool and warm (the catalog should indicate this but if not look at your other catalogs). If you had two copies of one catalog, you could cut and paste and re-arrange them. For a list of seed catalogs, check out my page/tab entitled “seed catalogs” at the top of my blog site.

spinach seedlings

spinach seedlings

The other point I made on the radio show was that many times, people new to gardening are intimidated because they think they have to dig up the sod in the backyard, build raised beds, or install an indoor lighting system. There are some plants that will grow from seed in a simple container, outside.  The containers can be used pots from plants you have already bought at the nursery or new, as long as they have drainage holes. Some herbs and veggies can be grown in pots with as little as a six-inch depth. The plants listed below will grow easily from seed started outside, using potting soil from a hardware store or nursery. They are not particular about water fluctuations nor are they heavy feeders. The cool season for us in Virginia is end of March to beginning of May, sixty degrees to low seventies. The warm season is after the average last frost, which is around Mother’s Day, low seventies to eighties.

Cool season, six-inch depth

Chives, Cilantro, Lettuce, Radishes, Scallions, and Spinach

Cool season, twelve-inch depth

Broccoli raab or rapini; Carrots, baby; Dill, Kale, Mibuna, Mizuna, Mustard, Mache, Nasturtium, Pak choi, Peas, Swiss chard, and Tatsoi

radish

radish

Warm season, six-inch depth

Basil, Chives, Lemon balm, Radishes, and Scallions

basil

basil

Warm season, twelve-inch depth

Beans, bush; Carrots, baby; Nasturtium, and Swiss chard

If some plants are listed in both cool and warm season, it is because they can tolerate both if slight adjustments are made such as cooling them down in the summer with morning sun and afternoon shade or starting new seed again throughout the gardening season. For more information on the plants, consult your seed catalog. Pick a few from this list that you are most interested in eating and order the seed packages for next year. To save on costs, find a seed buddy so you can share the seeds from each packet. You too can grow an edible garden!