Q: We have been growing tomatoes in the same place about 10 years and each year they are getting worse. Sue, we have very poor quality and quantity. Small plants. We try Miracle-Gro but even that doesn't seem to help. What can I do to improve the nutrients of the soil and get better plants?
A: The first suggestion, often difficult in the small backyard garden, is to move the tomatoes. I know it sounds too simple but many of the things that cause problems for tomatoes winter over in the soil.
Tomatoes and their kin (potato, peppers, eggplant, tobacco, petunias and tomatillo) should be rotated so that they aren't planted in the same area within three or more years of the last planting. Common soil borne problems include:
Wilts from soil fungi: Verticillium and Fusarium wilts.
Virus: Tomato/Tobacco mosaic virus survives in the soil and can infect transplants with the virus.
Nematode, root rot: stunted plants with pale green leaves; roots have multiple swellings. The tiny worm winters in soil or plant debris.
Other things that may cause problems include:
Inadequate sunlight: Fruiting plants need full sun for peak performance; Six to 10 hours daily, six is a bare minimum and far from ideal.
Water: Too much or too little. Too much leads to rotting, fungal problems, cracking and splitting; too little can cause stunted plants, poor nutrient uptake.
Toxins from the roots of black walnut and butternut trees are another source of wilting, particularly in tomatoes. Avoid planting within the root zone of the tree. Blossom-end rot -- a calcium deficiency but usually caused by either uneven watering or improper pH, both can affect the ability of the plant to use the calcium available in the soil.
Over-fertilization: Applying too much nitrogen (the N of the N-P-K on a fertilizer bag) will cause excessive foliage and few flowers. Consider fertilizing before the tomatoes bloom and again after the first harvest.
Cool temperatures: Planting too early risks frost damage, stunted growth, delayed growth. Plant outside only when the danger of a late frost is past and the soil has warmed. Early planting will require protection such as cloche, water wall or other heat-conserving devices.
Pests: Hornworms, stinkbugs, aphids, whiteflies, cutworms. Check plants often and treat as soon as discovered. Often, handpicking is the easiest option and quite effective.
Amend soil. Improve the organic content of the soil by adding compost, aged manure or other soil conditioners. This will increase the texture of the soil, its water-retention ability, as well as the amount and variety of microorganisms in the soil. Some of these combat the soil-borne pests that winter over in the soil. Do this now as soon as the soil can be worked.
Consider raised beds: Creating a new bed with fresh soil should lessen the chance of soil-borne problems.
Water at the base: Water in the early part of the day so the plants have a chance to dry off. Avoid watering the leaves as this can stir up fungus spores and spread problems.
Water during dry spells: the soil should be uniformly moist, not wet.
Grow resistant tomato varieties: Look for A=Alternaria, F=Fusarium, N=nematodes, T=Tobacco mosaic virus, and V=Verticillium on the plant tag or seed description.
Fertilize: Give plants a good start with an initial dose of weak fertilizer (starter fertilizer strength: 2 tablespoons of 5-10-10 or 5-10-5 per gallon or a weak fish emulsion) when transplanting out to the garden.
Readers: write in with your success solutions to this tomato problem.
Sue Kittek is a freelance garden writer. Send questions to Garden Keeper at firstname.lastname@example.org or mail: Garden Keeper, The Morning Call, P.O. Box 1260, Allentown, PA 18105.
THIS WEEK IN THE GARDEN
Indoors for transplant: Finish sowing dahlia, larkspur, portulaca and head lettuce. Sow: Leaf lettuce, peppers and tomatoes. Next week sow: cucumbers.
As soon as the soil can be worked, sow outdoors: peas and sweet peas, potatoes, poppies and mignonette.
Pot dahlia tubers and grow on indoors for cuttings in April.
As hostas peak through the soil, dig and divide large mounds.
Clear iris beds and cut back plants to about four inches to deter iris borers.
Purchase onion sets for planting later this spring.
Consider building a cold frame. It will extend the garden season by a few months.
Do soil tests before amending soil with anything other than compost.
Cut back old, dead foliage from perennials. Clear spring bulbs from leaf litter and mulch. Clear branches, twigs and other debris from the yard and garden beds.
Move plants wintering over into lighted area and increase watering as they break dormancy.
Clean, groom, divide and repot indoor plants so they are settled in before they move outdoors for the season. Remember root pruning can be used to control the size of a plant.
Continue to feed birds regularly and provide fresh water. Encourage nesting as part of any insect control program.
Map and plan changes to old beds or design new ones.