Tomato Tips

Healthy Tomatoes

Tip description

Tomatoes are one of the most popular vegetables in home gardens, largely because of the taste difference between a homegrown tomato and a store-bought tomato. Here are a few things to watch out for to keep the plants healthy. Regular watering helps nutrients flow throughout the plant and can prevent blossom end rot. Clean soil and sanitation reduce the common Verticillium wilt in which lower and older leaves turn yellow and brown. And russet mite, where lower leaves and stems appear a greasy bronze, can be controlled with sulfur dust.

Managing Pests and Diseases of Tomatoes

Months applicable

July
August

Category

3. Pests and Diseases

Late Tomatoes

Tip description

Tomato blossom

How many more edible tomatoes can you expect to get this year? Any tomatoes currently on the plant are likely to ripen nicely in the next month or so. Current blossoms may lead to good tomatoes, mealy tasteless tomatoes, or none at all. It depends on the weather. Many of us have taken the gamble and eaten tomatoes into December and beyond, more for the challenge and bragging rights than for exquisite flavor. But a cool fall can affect production and quality, and some gardeners start removing blossoms now. This allows the plant’s energy to go into the existing fruit. If we have another mild winter like last year, the plant could survive and produce another crop of tomatoes next summer. We each make our own decisions based on our guesses, hopes, energy level, and available garden space.

More information: Growing tomatoes in the home garden

Months applicable

September

Category

1. To-do

Tomato blossom end rot

Tip description

Tomato blossom end rot A brown depression on the bottom of tomatoes is usually blossom end rot (BER). This disorder is related to a calcium deficiency aggravated by irregular watering. Since most soils have adequate calcium, watering is usually the problem. Without regular watering, the calcium in the soil cannot reach the plant. Mulching can help. Water tomatoes regularly. Avoid flooding them so the roots sit in water. For more detailed information about BER please view Managing Blossom-End Rot in Tomatoes and Peppers.

Months applicable

July
August
September

Category

3. Pests and Diseases

Tomato Bottom Scarring

Tip description

Tomato bottom scarring

Sometimes scarring can be seen on the bottom (blossom end) of tomatoes. This can be caused by weather conditions such as cool and cloudy weather at bloom time, making the blossom stick longer to the small fruit. The fruit is perfectly good to eat with the damaged part cut out. Some large heirloom tomatoes are more susceptible to this condition.

Also known as catfacing.

Months applicable

June
July
August

Category

1. To-do

Tomato Hornworm

Tip description

Hornworm on tomato plant by Jack Kelly Clark

Both tomato hornworms and tobacco hornworms can do significant damage to tomato plants. They can eat entire leaves and take bites out of the fruit. Although they are large with a striking appearance, they camouflage themselves well on plants and can be surprisingly hard to find. Once you see one, you’ll wonder how you missed it. The first clue to their presence is often a pile of frass (insect larva excrement) on the leaves or ground under the pest. They are up to four inches long so they are easy to handpick for disposal. If you see a row of white eggs on their backs, those are from a parasitic wasp that will take care of the problem naturally. They are striking, with white striping and little round circles. The caterpillars get their name from the horn on their back end, and they are the larval stages of rather large brown moths.

More information: Tomato Hornworms

Months applicable

June
July
August

Category

3. Pests and Diseases

Tomato Russet Mite

Tip description

Tomato russet mites deplete juice from the cells of leaves, stems and fruit. They usually start at the base of the plant and move upward. If not controlled, these pests can kill plants. At first sign of damage, treat with sulfur dust or a spray solution of wettable sulfur and spreader-sticker. More information is found in the UC Pest Note on Tomato Russet Mite.

Months applicable

June
July
August

Category

3. Pests and Diseases

Tomato Staking

Tip description

It's time to start planning how you will stake your tomatoes. You will want to stake your tomatoes right after you plant your seedlings. Here are the various Tomato Staking Techniques we have tried.

Months applicable

April
May
June

Category

1. To-do

Tomato Suckers

Tip description

Tomato suckers grow from leaf axils, Cornell University

Pinching out suckers is recommended for areas with a short growing season (for faster production) or humid summers (to improve air circulation) or to make it easier to tie plants to stakes. But with our dry climate and long growing season, there’s no need to remove them if you’re growing tomatoes in cages. Letting suckers grow provides foliage cover to shield the fruit from direct sun, gives additional photosynthesis, and will produce more fruit. Feel free to remove interior leaves that are shaded out or turning yellow, or clip foliage as needed to make the tomatoes easier to find and harvest. But no need to pinch out the suckers.

See Cultural Tips for Growing Tomatoes for information such as site selection, soil preparation, when to plant, etc. when growing tomatoes.

Months applicable

April
May
June

Category

Watering Tomatoes

Tip description

If you haven't already, it's time to cut back on watering tomatoes. Tomatoes have far more flavor when the ripening fruit is deprived of water. Don't forget to remove competing weeds from around the garden.

Months applicable

July

Category

1. To-do

Tomato Tips

Tomato Tips for All Months