by Lis Friemoth
The perfect tomato
Gardening myth or real thing?
Now that I have your attention, we should acknowledge that there is no such thing as a perfect-looking tomato. You can get close, but as with all things in nature, perfection should be a goal, or a state of mind, not an appearance.
What most gardeners should realistically be looking for are fruits with limited cracks, scars, discolored puckering, spots and/or critters living inside. Toward that end, a good use of time is to focus on choosing good plant material, careful preparation of an appropriate spot in the garden, provision of quality plant care and frequent monitoring for early detection of any insect and disease infestations. Do keep in mind that nature always has a way to thwart our best efforts, so keep your end goals reasonable.
Good plant material should satisfy your taste buds and also be disease-resistant. Understanding plant health pressures in your garden will help you to choose that right material. Soil-borne pathogens, such as Fusarium and Verticillium wilt, can be completely devastating to plants that do not have any resistance. If affected by either of these pathogens, tomato plants will wilt and decline throughout the growing season, often to the point of death.
If those pathogens are present in your soil, it is essential that you look for and purchase cultivars that have an “F” or a “V” after the name. This indicates a plant resistance to these problems.
When selecting the right spot in the garden for tomatoes, be sure to rotate away from all other crops in the Solanaceae family (e.g. eggplant, potato, and pepper) for at least four years. This time frame will lessen the pressures from insects and diseases that are common to all of the family members. A pH in the neighborhood of 6.5 is necessary to keep the plant system running efficiently and allow for easy nutrient uptake.
Soils with adequate organic matter generally do not need much in the way of preplanting amendments. For clay soils, adding some large-particle material such as peat or well-composted manure may help to increase air and drainage capacities.
Six to eight hours per day of full sun is optimal for top production and fruit quality. Less sun will produce less fruit on plants of lesser vigor. All plants under less-than-ideal growing conditions will require more attention.
Gardeners get anxious to plant early, but the cool nights will limit the amount of growth on tomatoes. In fact, 20-degree swings between day and night temperatures will set them back quite severely. Even though they will survive nicely under cooler conditions — anything above 55 degrees F – they will not really thrive until air temperatures are consistently much higher. They are, after all, a tropical plant.
Care of tomatoes is really quite simple. Put them in after last frost and watch them grow, slowly at first, then like lightning. Lots of sun, a consistent water supply, a bit of staking and some pruning — if you want to — are all it takes to get a crop of about eight or so pounds per plant.
For good levels of available nutrients, a low nitrogen fertilizer may be worked into soil a few weeks before planting. After that point, no fertilizer applications should be made until after the flowers have set. Any applications of nitrogen prior to flower set will divert systemic sugars from fruit production to vegetative growth. Once the sugars are pointed to the fruit, fertilizer can be used to side dress the plants and bolster the crop.
When planting, be sure to space plants far enough apart to allow good airflow. This will help to keep pathogens moving, limiting airborne infections. Water needs for vegetables are about the same as all other plants — the equivalent of one to two inches of rain per week. What the plants do not get from Momma Nature, the gardeners in charge should provide. It is always a good idea to water deeply and infrequently, encouraging root growth to deeper levels.
Fruit cracking results from too much moisture, especially during high-growth periods. Septoria leaf spot and early blight show up, generally, just after fruits have set, although the leaves will become infected whenever conditions are right. Both will result in leaf spots, Septoria will present light-colored interiors with a darker edging. Early blight will have spots with a darker interior — on the fruit it appears dark and sunken with concentric rings around the stem end.
Pruning tomatoes often is a topic for intense discussion among home-production veggie growers, and there are good arguments on both sides of the issue. From my perspective, there are two types of pruning that are useful. The first is once fruit begins to set. Removing all of the branches, stems and suckers — whatever is green and growing — that is lower than the lowest fruit set will get the sugars to the fruit without any diversion to extraneous leafy tissue. The second is at the end of the season — September or so depending on the weather. That is a great time to remove the stem tips to stop the vegetative growth. Doing this will refocus carbohydrates to the existing fruit, speeding up the ripening process.
The timing recommendation for this pruning technique is generally about four to six weeks before the first hard frost — cultivar-dependent, of course. Ultimately though, if you want to prune, prune. If you don’t, then don’t bother; tomatoes will grow either way.
— Lis Friemoth is a horticulture diagnostician. Contact her at (262) 745-2904, P.O. Box 58, Springfield, WI 53176, or e-mail her at gardenhoe@tds.net. |
