Tomatoes are prone to a so many diseases and pests, including viral, bacterial and fungal assailants. Keeping your plants healthy goes along way in helping prevent disease. Start by planting disease resistant-varieties. Training and trellising helps maintain airflow and keeps the fruit off the ground where the disease spores hide.
Minimize Irrigation: Tomato plants have surprisingly low water needs and overwatering can promote disease. Once the fruit has started to form, water only when the top three inches of soil becomes dry and the leaves look limp in the heat of the day.
Water at Ground Level: Little can be done about water that falls from the sky, but don’t add insult to injury by showering your tomatoes with a sprinkler—fungal diseases only spread when the plants are wet. Instead, use drip irrigation or a soaker hose to water at ground level.
Water in the Morning. This way, the moisture will evaporate quickly from the surface of soil, giving the roots the water they need, but keeping the humidity down around the plants.
Use Straw or dried leaves to mulch your tomatoes. Mulching helps by covering the fungal spores. Mulching also conserves moisture in the soil, so you don’t have to water as much.
Remove Infected Leaves Immediately. Don’t hesitate to clip off leaves as soon as any spots or deformation is apparent—it may save the rest of the plant from succumbing to the disease. Dispose of these clippings far away from your tomato plants.
Prune Out Dense Foliage. Tomatoes tend to grow more thickly than is necessary, reducing air flow and producing more foliage than their immune systems can support. Prune out new sprouts that emerge from the main stems once fruit has begun to develop and train the plants to an open, spreading form.
Keep Adjacent Vegetation Down. A thicket of weeds or a tall patch of corn or beans next to your tomatoes blocks airflow and keeps the humidity high at ground level. Ideally, tomatoes should be planted out in the open with nothing but mulch, turf grass or other small stature crops (like basil or garlic) around them.
Disinfect Tomato Tools. Anything that you use to prune diseased tomato plants or to work the soil around them should be disinfected before using on or around healthy tomato plants (plants in the tomato family, which includes peppers, potatoes and eggplant). Dipping the tools in a 10 percent bleach solution or full-strength rubbing alcohol is effective.
Control Insect Pests. Tomatoes are rarely destroyed by insects, but they are frequently attacked on a small scale, which weakens the plants and makes them more susceptible to disease. Some insects are also responsible for spreading diseases. Small sucking insects (like scale, aphids and mites) can be dispatched with all-natural insecticidal soap. Larger bugs (like hornworms and stinkbugs) can be picked off by hand. Check the stems and both sides of the leaves if you see signs of insect damage.
Fertilize. Tomatoes are heavy feeders and will have greater disease resistance with a few boosts of fertilizer during the growing season. Once the fruit has set, apply a high phosphorus fertilizer every three weeks.
Most tomato diseases cannot be stopped once they are entrenched. There are fungicides and bactericides that can help, but they are only truly effective when applied as a preventative. There are products registered for use by organic farmers, such as copper sulfate, which are naturally derived but are still highly toxic. Organic farmers are only allowed to use those substances in extreme cases when they have documented that no other measures have been effective and they are in danger of significant economic losses if the disease were to progress.
Some home growers claim that piercing the base of the tomato plant with a strand of copper wire imbues them with antibiotic properties that keeps diseases at bay, though there is little scientific evidence to support this theory. Other home remedies range from hydrogen peroxide and baking soda sprays to applying a slurry of skim milk or just feeding the plants chamomile tea. While there may be merit to some of these approaches, waging war with tomato diseases is rarely a winning battle, making prevention the best cure.
Tomato Farming Part Five: Harvesting and Selling
Within two months of transplanting tomato seedlings, the fruit should be filling out and starting to turn color and ready for harvesting.
It’s best to cut them off with scissors or hand pruners with a short stub of stem attached—otherwise the area around the scar at the top may rot before you have a chance to eat.
Contrary to popular belief, tomatoes ripen just as well off the vine as long as they are picked in a ‘mature green’ state, which means that the seeds inside the fruit are fully developed. Green tomatoes may be picked once they’ve reached their maximum size and have begun to show the first blush of color on their skin.
There are several circumstances where picking a tomato before it is fully colored makes sense:
– Some varieties, especially heirloom varieties, are prone to cracking around the crown of the fruit, which leads to premature rotting. Picking them before they crack avoids the problem altogether.
– Tomatoes will not color up when temperatures are consistently above 86 degrees and will rot on the vine in the green state. Bringing them indoors allows them to ripen fully.
– Cool rainy weather exacerbates the fungal diseases that tomatoes are so prone to. If the fruit begins to rot as it colors up, bring plants in when green.
Tomatoes do not need to be in a sunny window in order to ripen. In fact, they ripen much faster if placed in an enclosed space since they emit ethylene gas as they ripen. The greater the concentration of ethylene gas around the fruit, the faster and more fully they will ripen. A cupboard, paper bag or between sheets of newspaper are good places to ripen tomatoes indoors. They need oxygen to ripen, so don’t seal them up in a plastic bag or Tupperware. And above all, don’t put them in the refrigerator—they will not ripen at temperatures below 65.
Green tomatoes ripen indoors in approximately two weeks. To speed up the process, put a ripe banana or cut-open apple in a bag with the green tomatoes—both emit lots of ethylene gas.
Once tomatoes have fully ripened, they can be kept for up to four weeks at 55 degrees before they start to decay. They may last even longer in the refrigerator, but they turn bland and mealy when kept below 50 degrees.
Selling Your tomatoes
It is important to prepare your marketing well ahead of harvesting. Look for who or where to supply the product. This is because, tomato is a perishable product unless you have built storage system.
I will recommend selling in bulk especially if you have a big farm. You can go to markets and supply at a wholesale (low cost). Tomatoes are usually priced and sold in baskets.