Chapter 7
From Seedlings to Transplant
When the tomato plants have at least one true leaf, they should be transplanted and placed in a cool (55˚ to 65˚) environment. As the seedlings grow, continue to transplant them into larger containers, each time planting them as deeply as possible in progressively larger pots. Seedlings should be transplanted when the height of the seedling is three times the diameter of the pot. The seedlings should not be touching one another as this tends to make them grow straight up rather than spreading out. Aim toward transplanting the seedlings at least twice before placing them outside in the garden. This will prevent their becoming leggy and will assist them in developing a strong plant base. Keep in mind that your plants will need to be tall enough with a strong base so that you can place them 12 inches into the ground when you transplant them. If you find that your plants become tall but not sufficiently wide, you are either not providing them enough light, over watering, or fertilizing them excessively.
Water the plants as necessary using a diluted fish/seaweed mixture; follow the instructions on the container (usually 1 tablespoon per gallon of water). Some growers add 1 teaspoon per gallon of Miracle-Gro 15-30-15, as well. Whatever water-soluble fertilizer you decide to use, it is important that it be a very diluted mix, something like 1/4 of the recommendation on the package. Bottom watering is best. This is done by placing an inch of water in a flat rectangular container and then setting your plants in the water for five minutes, allowing them to suck up the water they need. If you are not bottom watering, soak the growing mix in your containers and then allow it to become nearly dry before watering again. One way to tell when your plants need water is to lift them and see what they weigh. You will quickly learn to tell when your plants need water, and if they have been watered adequately using this container weighing technique.
Keeping tomato plants indoors under grow lights is difficult. To avoid this, don't start too early. Having access to a heated cold frame or a small greenhouse allows for an early start. Plan your starting date so that the transplants reach a reasonable size at a time when the weather is suitable for outdoor planting (usually after danger of frost has passed).
What is Photosynthesis?
Plants need energy to survive. Plants are capable of absorbing energy from sunlight and using it to produce sugar by a process called photosynthesis. Using photosynthesis plants convert light energy captured from the sun or an artificial source into sugar that can be used later to provide energy for the plant's growth. Photosynthesis involves converting carbon dioxide and water and light energy into sugar. This sugar is then used by the plant to provide energy for growth.
Grower Comments on Going from Seed to Transplant
"It is very important to never let transplants touch each other. This will cause them to stretch. They are always fighting for light. If the plants seem to be stretching a bit, lower temperatures. You can go down to 55˚ to 58˚ at night and 65˚ to 70˚ during the day. Watch your watering. As far as your fertilizer requirements, half strength 20-20-20 every 5 to 7 days should be fine once the seedlings have emerged." Minnie Z.
"I start my seeds in a mini greenhouse that can be bought at any garden shop – nothing real fancy, just the round peat pellets (Jiffy 7's) in the greenhouse. Once they sprout and are around 2 inches high, I take the netting off the peat pellet and place the seedling in a 4 inch peat pot with 1 inch of potting soil in the pot. This leaves 3 inches of space in the pot to backfill around the plant. I then place them under grow lights. I prefer to use the florescent type because they stay cool and I can allow the plants to actually touch the light. Doing it this way helps keep my seedlings from getting too leggy. The seedlings will remain in these 4 inch pots until transplanting. As for fertilizing, I only use a diluted seaweed mixture as a foliar spray while the plants are inside. The box I use to harden-off my plants is pretty simple. It's 6' x 6' x 4' high, made of 2 by 2 inch lumber and wrapped with a shade fabric that allows 60% of the sunlight in. I keep them in this for about 10 days, with the lid coming off for a few hours each day during the last 3 days." Paul H.
"I grow my plants in the house. I start my seeds 4 weeks before my planting date. I put up a 4 by 8 foot starting table in a spare room that has an 800 watt full spectrum grow light. I run the light for 15 hours a day. I leave the heat at about 75˚. I start my seeds in peat pellets and transfer them to one gallon pots as soon as any roots show. I leave a fan blowing across the plants the entire time they are inside to strengthen them – turning the plants 1/4 turn every day. I use a modified version of an ebb and flow system to water and fertilize the seedlings – keeping an eye out for salt accumulation on top of the soil." Ron W.
"I start my seeds on a heating pad or on top of our heating vents if I start early. I may need to start later to hit the October 1st contests. As soon as they begin to sprout, I place them under grow lights in my germination box, which is painted white inside. I water as needed and foliar spray, alternating week to week with kelp and Miracle-Gro, each diluted to half the recommended strength. When they're about 4 inches high I transplant up to last set of true leaves in 4 inch pots. When they get root bound I transplant into 8 to 10 inch pots. I always water them when transplanting. I like my transplants to be the largest three or four out of a dozen – thick stems and dark green foliage. I give the rest away. I harden them off the first day for a few hours of daylight. After that, all day on the porch unless a frost is forecast. While hardening them, I give them water regularly, because wind and sun can dry them out quickly. Nothing else special, I don't have a cold frame or greenhouse." Don C.
