Here are a few of the terms youʼll encounter as you grow Americaʼs favorite vegetable.
A tomato variety bred to combine the desirable qualities (color, taste, disease resistance, etc.) found in the parents. Early Girl, Better Boy and Sungold, the worldʼs favorite tomato, are a few examples. As it is not yet stabilized, seed saved from a hybrid is not guaranteed to produce the same tomato if planted out in future seasons. Hybrids often suffer from the “cardboard-tasting tomato in January” reality or reputation but when a) grown in your home garden, b) grown correctly and c) picked when itʼs ultimately ripe, most will provide thrilling tomato taste.
While there are several different kinds of heirloom classifications the quality common to all heirloom varieties is that they are open-pollinated. Properly saved seed from these plants will produce the same tomato in future seasons. Though some are modern, others have been around for hundreds of years and have truly been handed down from generation to generation. (Mortgage Lifter, Green Zebra, Black Krim, Giant Syrian)
Determinate (D or DET)
This tomato class produces fruit on the top or end of the main stem. When that happens upward growth ceases, so as a result his class tends to be smaller, tidier and sometimes wonʼt need staking. Donʼt pinch aggressively, as the side branching will be productive. More fruit on a determinate plant will be ripe at the same time, making it practical for making sauces and other kitchen use.
Indeterminate (I or IND)
Generally larger and rangier than determinates, the indeterminate tomato plant will not flower on the terminal or main stem so that stem continues to grow. The plant fruits on side branching that grows off the main stem, providing steady production all through your growing season.
Days or Days to Maturity
The approximate number of days from planting to harvest. This assumes youʼre planting a six week old seedling, which is more or less what will be offered at planting time in the spring. While certainly not an absolute, the “days” will help you develop your own strategy for early, midseason and late summer harvesting.
Organic matter added to your garden area that increases bulk, nutritional value and the soilʼs drainage potential. Often purchased in bags at your local nursery, your homemade compost is also a perfect amendment. Tomatoes will enjoy soil that is rich with organic matter, as most plants do. Amend your vegetable garden all year long!
Any material or materials added to or laid on the top of the soil around your plants to further insulate, protect and aid in weed control. Hay, plastic sheeting, bark chips and yesterdayʼs newspaper can all be used as mulch.
Food for your plants. Granular, liquid or pelleted, fertilizers provide the main nutrients needed for growth, vigor and fruit production: Nitrogen (N), Phosphorus (P) and Potassium (K). Those are the three numbers on the front of the fertilizer bags you just purchased! For tomatoes look for a more balanced formulation. The numbers should be in the same range. Fertilizer showing 30-0-0 is lawn food!
The (optional) act of thinning or “pruning” your tomato plants. Pinching means removing new side growth from where it starts, just above where the leaf meets the stem. This thins the plant to let more light and heat in, makes it more manageable and channels the plantʼs energy, usually resulting in larger fruit.
Left to their own devices thicker, bushier plants will produce more fruit but it will be smaller or fruit size will be less uniform. Some people pinch religiously, others, (like me) donʼt pinch at all because itʼs too much work!
Pinching is often a regional strategy. Growing where itʼs cooler? Pinch more. Are you in a hot spot? Pinch less, your plant and ripening fruit will need the cover. See notes on tomato classes above (DET and IND). You wonʼt want to pinch your determinate plants much – or at all!
Blossom End Rot
The tomato ripens with a brown bruise-like section on the blossom end (opposite the stem). Most often happens at the beginning of the season before temps rise and even off. Some varieties, Roma types in particular, seem to be especially susceptible. Long thought to be due to a calcium deficiency (add soil/hort calcium products, gypsum or egg shells to the garden if you find out this is the case) itʼs now widely accepted that early season stress (inconsistency in weather, water, fertilizing) is the cause. Mulch heavily, donʼt overfeed and water deeply and infrequently to best prevent this situation.
These degree-like letters on a tomato label (hybrids and some open pollinated varieties) offer clues to diseases or conditions the plant shows some resistance to. V (verticillium wilt), F (fusarium wilt), N (root knot nematode), T (tobacco mosaic virus).
Verticillium and Fusarium Wilt
Systemic diseases typical to specific regions, almost impossible to control. The entire plant is weakened (looks wilted quite suddenly, often shows yellowing leaves), limited dramatically or killed by the disease. Soil-borne so move your garden if you can!
Early and Late Blight
Early blight is exhibited by spotting/yellowing/defoliation of the leaves from the ground up. Best prevented by planting at wider intervals to allow more air circulation and careful water management. The plant can still produce but may be compromised.
Late blight is not curable and was the scourge of east coast gardeners in 2009 after a really wet spring and summer. Will not overwinter in colder areas but clean up the garden judiciously anyway! Follow the preventative measures mentioned above, stay vigilant and remove any leaf that begins to show signs of disease and if youʼre growing potatoes in the garden remove them! The disease will be persistent in potato roots and tubers.