Starting your own vegetable transplants

Story and Photos by Denise Pugh

As winter fades and spring is approaching, evidenced by the yellow blooms of Narcissus, one begins to dream of fresh vegetables. You think of the ‘Brandywine’ or ‘Mortgage Lifter’ tomatoes from last year’s garden, or the sweet Italian peppers with just the right amount of sweet and hot, but you can’t find these transplants at local garden centers. So why not try growing your own?

Soil blocking is an excellent way to start seeds; it reduces waste and prevents transplant shock. The mold shown here is widely available at most garden centers.

Starting seedlings is a combination of science and art. Since growing seedlings takes a commitment of time, choose varieties that you want the most but cannot find locally. Purchase seeds from reputable suppliers. Once you’ve purchased your seeds, read the information on the packets – most include when to start indoors, recommended planting depth, optimal germination temperature, days to germination, and days to harvest. Check to see when the seeds were packaged – those dated this year will have better germination rates. If you have stored seeds from previous years and would like to assess their germination potential, place ten or so seeds onto a damp paper towel. Fold the paper towel over top of the seeds, place in a zip lock bag labeled with the date and type of seed, and put the bag on top of your refrigerator. Check the bag after 10 days to see how many seeds germinated: that will give you a rough idea of the germination rate/percentage for that packet.

Soil blocks allow growing many transplants in a very small space.

As far as containers, there are many options – and I have had equally good results from cell packs, peat pots, and soil blocking. Seed-starting kits and peat pots are available at most local garden centers. Bags of sterile soilless mix or other medium labeled “seed starting” or “germination” mix can usually be found close by. For soil blocking, the mix is a bit denser to enable it to hold its form in the soil-blocking tool. 

Water from the bottom and use a kitchen baster for maximum control of delivery.

One of the most useful tips is to add water to the medium to the point that it is thoroughly moist, but not wet. Since many mixes are mostly peat, it may take some time to hydrate the medium. Partially fill the containers with the moistened medium, tamp lightly and press to remove air pockets, and then fill the containers almost to the top. I use an unsharpened pencil to make a small hole, and then plant at the depth recommended on the seed packet. (I put two seeds into each cell.) Next, place the trays into a large plastic container on a seedling heat mat and cover with the lid to hold in moisture during this phase. Seedling heat mats are particularly helpful for tomatoes and peppers. 

At germination, the plant will have two leaves, which are called cotyledons. These are not true leaves; the next set of leaves are considered true leaves. At this point, I remove the heat mat and place the seedlings not very far under the grow lights. This intense light prevents the seedlings from becoming leggy. Use a ceiling fan or small desk fan to increase air circulation around the seedlings. This will reduce damping off (a fungal disease prevalent with new seedlings) and strengthen the stems.

Grow lights should be just a few inches above the seedlings to prevent them from becoming leggy.

Seedlings should be watered from the bottom, which is why I use a kitchen baster to direct the water to the desired area without splashing. Once the seedlings have their second set of true leaves, you can feed them with half-strength liquid plant food. At this point, I transplant the seedlings into a larger container or soil block if they’re outgrowing the current one. 

These tomatoes are ready to be “hardened off” for spring planting.

When the seedlings reach 2-3 inches tall and have two sets of leaves, if the weather is mild, you can begin the process of “hardening off.” This is a one or two week(s) process that requires taking the seedlings outside and setting them in a protected, shady/dappled sun location, increasing the length of time they spend outside every day. I start at two to three hours, then progress to five hours, then seven, then morning until evening, and finally overnight. I am careful to protect these tender plants from strong winds, direct downpours, or harsh sun. Your plants will grow a bit sturdier each day, and once nighttime temperatures are consistently above 55 F, you can transplant them into the garden.

Read your seed packets to determine days to harvest and recommended spacing. Protect your tender seedlings from rabbits, insects, and harsh winds until they’re well established. 

Final step – enjoy the taste of summer from your own backyard.




Seeds to Start Indoors:
Brussels sprouts

Seeds that can be sown indoors or in the garden:

Seeds to sow directly into the garden:
Spring onions

• Cell packs, peat pots, soil block, or trays
• Planting medium: seed-starting mix or soil-blocking medium
• Heat mat or warm sunny windowsill
• Light provided by grow lights or a window
• Watering can (a kitchen baster works great)
• Seeds
• Labels and permanent marker to label seed trays

Mail-order sources:
Johnny’s Selected Seeds, johnnyseeds.com
The Gardener’s Workshop, thegardenersworkshop.com
Renee’s Garden, reneesgarden.com

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