Cool-season seedlings like cabbage can be planted outdoors in early to mid spring.
Winter’s end is in sight—with or without favorable predications from the groundhog. For months you have been eating frozen veggies, imported salad greens, and tomatoes that taste like Styrofoam. It is time to think about an activity that is fresh, exciting and pro-active; something that will get your hands in contact with soil and ultimately, get your taste buds in contact with something delicious. It’s time to start veggies from seed!
Love It, Choose It
Seed catalogs carry some of the most interesting and wonderful vegetable varieties. (image by Jessie Keith)
What’s best to plant from seed? Almost any type of vegetable will work, but some work better than others. [Click here to discover our favorite spring vegetable varieties!] Among the best are beans (bush or pole types), beets, carrots, corn, peas, radishes, spinach, and turnips. Other possibilities might include herbs like basil; various greens and cucurbits, including squashes, zucchini, and cucumbers. The best advice about plant choices is also the oldest: grow what you like to eat. There is no point in starting radishes or mustard greens if you and your family will turn up your collective noses at the finished crop.
Another good piece of advice: if space is limited, choose compact varieties and/or truly special heirloom varieties that you can’t purchase as seedlings at the garden center. Seed catalogs are the best source for wonderfully diverse vegetables. Seed sources like Johnny’s Selected Seeds, Baker Creek Heirloom Seeds, Pinetree Seeds, Burpee, Parks, or Jungs all have great selections.
Lay In Supplies
Plastic cell packs are the best choice for seed starting (lettuce seedlings shown).
Once you have made your choices, lay in supplies. This need not be expensive. The seeds come first. After choosing your veggies, look at the package directions, which will give you an idea of the best times to start various species and varieties in different regions of the country. If you are starting multiple varieties, create a master schedule on paper or a computer spreadsheet.
Next, select your containers. Plastic cell packs are good and available at garden centers, nurseries, and big-box stores. However, you can also use egg cartons or other containers, as long as they are clean and have drainage holes in the bottom. Disinfect containers with a mixture of one part household bleach to nine parts water and rinse and try them thoroughly before using.
OMRI Listed mixes are best for vegetable seedling cultivation.
Strong plants require a good growing medium. Fresh, soilless mixes are best, like Fafard® Natural & Organic Potting Soil and Black Gold® Seedling Mix. Both are OMRI Listed® for organic gardening and yield great results.
Our potting mixes contain an all-natural wetting agent, so there is no need to pre-wet containers before planting. Fill the containers with the seedling mix, leveling the mix about one quarter inch below the tops of the containers. Follow the package directions for each seed variety, and be sure to label them as well as marking planting dates on your master calendar or spreadsheet. Save the seed packets for later in the growing cycle, when you will need them for spacing and other information.
Generally speaking, seeds should be planted to a depth equal to three or four times the diameter of the seed. Small seeds should be surface sown. Plant two to three seeds per cell, gently irrigate them (bottom water and then gently mist the tops), and place the containers under grow lights. Many seedling flats have clear plastic planting domes to create a mini greenhouse for the plants. If you lack these, cover your pots with plastic wrap and poke a few ventilation holes in the plastic. (These should be removed once your seedlings have emerged.)
Warm-season veggies like peppers grow faster and better with gentle bottom heat.
Place the plastic-covered containers in a location where they will receive warmth and light. (At this stage, high sunlight is not necessary, and may even “fry” the emerging seedlings.) Setting up a table with shop lights fitted with broad-spectrum florescent bulbs for plant growing is best. These bulbs provide gentle heat and light in the right spectrum for plant growing. Flats should be placed no more than 6″ from the bulbs for strong stem growth. Include a seedling heat mat or two for warm-season veggies, such as tomatoes and peppers, and you are in business.
If you lack grow lights and heat mats, a great place to start seedlings is on top of the refrigerator, where the seed trays will receive bottom heat. For the most part, starting with moist potting mix and a plastic cover will create a self watering system until the seedlings emerge, but check the trays regularly and don’t let them become dry. If condensation is forming on the plastic, the potting mix is probably moist enough.
Out of the Incubator
Thin seedlings so there is only one plant per cell or pot.
When your seeds germinate, liberate them from the “greenhouse” by removing the plastic. Watch and water sparingly, as needed, preferably from the bottom. Don’t drown your baby plants! Once they have developed a second set of leaves, thin crowded plants by snipping off weaker ones at soil level. You should only have one strong seedling per cell. Follow spacing instructions on the seed packet.
After you thin the seedlings, give your tomatoes or basil or cilantro what they crave the most—more light. A south-facing windowsill is good, but be careful not to place seedlings too close to cold glass. The other option is to simply raise the height of your broad-spectrum fluorescent light as your plants grow. Aim for about 15 hours per day of light to ensure good growth.
Out of the House
Gradual exposure to higher light and outdoor conditions will ensure your seedlings will be fully acclimated before planting.
Eventually the weather will warm up, all danger of frost will pass and your plants will be ready for the great outdoors. Like all major moves, this one should be gradual. “Harden off” your seedlings by taking a week and placing the containers outside, in a semi-protected spot with partial sun and low wind, for gradually lengthening time periods each day. Gradually increase the amount of light and exposure they receive until their stems become stouter and their leaves are fully adapted to long days of natural sun. Keep watering. At the end of the hardening off period the young plants should be ready for planting in the garden.
Little Seeds, Big Rewards
Starting veggies from seed is economical, gratifying and lets you harvest vegetables ahead of your neighbors. You will end up with greater variety, a more diverse harvest and—best of all for competitive veggie growers—big healthy bragging rights.