DECATUR – Every gardener can get an ample harvest of garden tomatoes, by following a few easy steps to prevent the most common problems and trellising their tomatoes when needed.

Most gardeners think blossom end rot, a black patch at the blossom end of your tomato, is caused by a calcium deficiency, but it is more likely caused by inconsistent watering. It is recommended to water your tomatoes at least 1 and a half inches per week and mulch at the base to conserve water. Inconsistent watering can also cause the tomatoes to crack when they are ripening.

Although tomatoes are heavy feeders, it is best not to overfertilize as too much nitrogen can cause problems with tomato production including decreased yield, damaged roots, and unnecessary vegetative growth. Start with a starter fertilizer at time of planting even if you have amended with compost. A starter fertilizer contains low amounts of nutrients. Any high-quality, complete fertilizer that contains at least nitrogen and phosphorus will work as a starter fertilizer. In the beginning plants nutrient requirements are low, and as they grow the requirements raise and lower once fruit has become full size. Use about a tablespoon of ammonium sulfur fertilizer per plant when tomatoes are the size of a golf ball. Follow up with a 10-10-10 fertilizer application every four weeks after that.

 Now as you peruse tomato varieties to grow this season, one of the first questions you should ask is "Are these determinate or indeterminate plants?" Each requires different planning.

Determinate (bush) varieties produce their fruits on the growing tips, causing the branch to stop production once the fruit has set. They are most often used for container gardening or small spaces and generally do not need to be trellised or staked. Examples of determinate tomatoes are Roma, Mountain series, Cherry Gold.

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Indeterminate plants produce their fruits on side branches off a main vine and are able to produce fruit all summer and fall until they are killed by the first frost. They can grow between six and twelve feet tall and require staking. They generally taste better than determinate tomatoes because of the foliage to fruit ratio. Some of the most popular heirloom varieties are indeterminate types: Brandywine, Cherokee Purple and Sweet 100.

For indeterminate varieties, trellising or staking plants is essential to keep the foliage and fruits off the soil and increase air flow, reducing foliage diseases. An upright plant also makes it easier to spot pests. There is nothing more disappointing than a gorgeous tomato eaten up or rotting because it has been lying on the ground.

Most gardeners stake their tomatoes at planting, or shortly after. Staking a half-grown tomato is an impossible task without damaging the plant. Basic tomato cages found at any big box store or garden center are the simplest, most popular, and most affordable method of trellising. However, these tend to topple over once the plant grows large, and they don't fare well against Illinois winds. These are more effective with smaller determinate varieties but are insufficient for indeterminate tomatoes.

A second method of trellising tomatoes is homemade wire cages. Home gardeners construct these out of rolls of 6-inch wire mesh, stacked and zip-tied double high to create an 8-foot tall column. The cages must be reinforced with at least one t-post, at least 6-foot-tall, and set in the ground at least 6 inches deep. This is the method used by Bill Davison, Local Food System and Small Farms Educator, because most of the work is done in the beginning of the season but requires more upfront cost the first year.

A third method, the Florida weave or basket weave, creates a hedge of tomatoes. This method costs less than wire mesh trellising, using less than half as many t-posts, but does require more labor throughout the growing season. One t-post is placed at the beginning of each row, and after every third tomato plant. Tightly secure twine to the post at the end of the row, 1 foot from the ground. Jute is recyclable and breaks down over time; polypropylene is stronger and more durable season-to-season; we prefer the latter. Snake the twine between the plants, pulling tight around the next t-post and securing it with a handful of wraps, before returning, snaking on the opposite side of each plant to secure it between the sections of twine. Additional rows of twine are added every 8 inches as the vine grows taller. All growth should be removed from the bottom 12 inches of the plant once the second row of twine is added. When the plants reach the row at the top of the t-posts, they can be pruned back for height.

If you would like to learn more about tomato care trellising, I will be posting pictures of progress throughout the season at facebook.com/MidIllinoisMasterGardener.

Macon County Master Gardeners are volunteers trained by Illinois Extension. Master Gardeners fulfill their mission of Helping Others Learn to Grow by volunteering their time and horticulture skills through community gardening projects and educational outreach.

Extension provides equal opportunities in programs and employment. If you need reasonable accommodation to participate, please call (217) 877-6042.