By Carl Wilson, Colorado State University Cooperative Extension agent, horticulture, Denver County
After mustering the physical and mental energy to dig the garden and plant tomato and other vegetable transplants this spring, it's natural to want to sit back and relax. Harvest of tomatoes, peppers and eggplant is a long way off, right?
While taking a breather is all right, you need to stay focused on the job. With full-season vegetables, the size of the harvest is determined by how you care for your plants in the early growth stages.
Two secrets will ensure good early growth. The first is to maintain regular fertilization. After transplants are established, begin applying small amounts of fertilizer every couple weeks. Any general purpose product containing 5 to 10 percent nitrogen will do, either in granular or liquid form.
The important thing is not so much what product you use, but fertilizing on a regular basis. This is where slow release granules can help out. They meter out fertilizer over a number of weeks or months for those who may forget or not want to reapply fertilizer regularly.
Why do these vegetables need a steady, regular dose of fertilizer early to achieve satisfactory harvests later? Because plants that grow vigorously from their early stages develop a good-sized plant frame on which a large number of fruit can set. Without fertilizer the plants develop a small stature plant that can hold only a few fruit. Irregular fertilizing causes plants to stop vigorous growth, remain small and put energy into developing fruit on the limited number of blossoms available.
One caution: Do not to overdo it. Too much fertilizer produces weak growth and may last too late into the summer. After mid-season, the plant frame is established for the year and fertilizing should be stopped.
The second secret to good early growth is regular watering. Water is necessary to carry the fertilizer within the plant and for normal growth. Interruptions in watering cause the plant to wilt, growth to be interrupted and may cause the plant to concentrate on fruit development instead of vegetative growth. Again, remember that more is not better. An excessive amount of water produces a plant response very similar to letting plants go dry.
While fertilizing and watering don't require great amounts of time, regular care will reward you with larger plants and bigger vegetable harvests later.
Photograph courtesy of Judy Sedbrook.
© CSU/Denver County Extension Master Gardener 2010
888 E. Iliff Avenue, Denver, CO 80210
Date last revised: 01/05/2010