Now’s the time to get ready to grow your own seedlings! It’s not really difficult, and can extend your growing season by many weeks. For example, by planting brassica’s (cabbage, broccoli, and cauliflower) in February in your basement under grow-lights, you can put large, sturdy transplants into your garden by the end of March or early April, and be eating them when others are just seeing them come up! However, remembering that photosynthesis, using light, heat and moisture causes plant growth, you must follow a few key natural principles very carefully, or you will be disappointed.
First, seeds must have moisture to germinate and grow. And the soil mix must be moist, but not soggy, or you’ll drown the new plant, since it must also have oxygen!
Second, while heat is essential, temperatures must be maintained in a narrow range for ideal germination to occur. Most vegetable seeds germinate quickly between 75 and 80 degrees Fahrenheit. After plants are up, many of them will grow in cooler temperatures, but most all will become dormant (stop growing) at temperatures below 50 degrees.
Third, light is not necessary for seed germination, but as soon as your seedlings begin to emerge from the soil, maximum light is required immediately for proper development. Therefore, to grow in your house, make sure your plants have a strong (but not hot!) light source directly on the plants, for up to 16 hours per day. Pictures of two grow-light shelves can be seen in the Photos section of the free gardening group at MittleiderMethodGardening@yahoogroups.com. The metal one is 6-shelf Commercial Chrome Shelving, from Sam’s Club costing only $70, and will hold 20 flats of plants. Suspend shop lights with 2 cool and 2 warm 40-watt tubes 2 to 4″ above the plants.
The fourth principle relates to feeding. A balanced nutrient mix of 13 minerals is essential to plants immediately after germination. Those nutrients are mineral salts and must be very dilute in the soil moisture, otherwise osmosis will cause the salt to draw the life-giving moisture out of the plants, and they will die. To ensure you never burn your plants, water seedlings daily using the “Constant Feed Solution” of one ounce (2 level tablespoons) of Weekly Feed dissolved in 3 gallons of water. For the Weekly Feed formula, go to Lesson 5 of The Mittleider Gardening Course book – www.growfood.com/shop
Next, it is important to separate your small plants before their leaves begin to overlap with others’, or the tiny stems will become very weak and spindly as the plants all stretch, looking for more light. By the time the plants have their first or second true leaves, this step should be completed. Failure to transplant them now, even waiting a few hours can result in spindly, weak plants, which never recover. Transplanting seedlings into 2″ 6-paks or pots or into 18″ by 18″ Flats or trays will provide adequate space for them to grow an additional 2-3 weeks, depending on variety. If it’s still too early to put them out into the garden by the time plant leaves are again beginning to overlap, prune the leaves, transplant again into larger pots, or separate pots, so the plant leaves always have maximum light.
Before transplanting into the garden, “harden-off” your plants outside, off the ground for 2 to 3 days, to acclimate them to direct sunlight, temperature, wind, etc. This is important so the plant doesn’t have the shock of a new environment added to the shock to its root system caused by transplanting. If the weather turns cold at night, bring the plants back in the house. The temperature adjustment needs to be gradual.
For many of your plants, the pruning process does double duty. In addition to assuring maximum light, it shocks the plant mildly, causing it to pause in its growth and produce a thicker, sturdier stem. This process makes the plant much better able to endure the vicissitudes of the outside environment, such as cutworms, ants, etc. that often quickly decimate plants with weak, spindly stems.
For tall-growing plants, like tomatoes, by the time they are 12″ tall, provide small stakes tied to the plant stem to prevent them from falling over. And with tomatoes, begin immediately to remove all sucker stems as soon as they appear, to assure a single, strong stem and maximum production from your plant.