Tomato Flowers But No Fruit - Why Is My Tomato Plant Not Fruiting?

Tomato plants will occasionally not produce fruit, even though the plants have plenty of flowers. If your tomato plants’ blossoms are falling off without any fruit setting, this article will help you identify the problem and provide some solutions for tomato plants that don’t set fruit.

Causes for Blossom Drop in Tomatoes

Despite being one of the most popular home crops, tomatoes have their share of sensitivities. They are extremely reactive to dips or increases in temperature, insufficient or excess irrigation, improper fertilization and pollination. All these can result in a plant that blooms but never fruits.

Heirloom varieties are more prone to blossom drop than modern cultivars. This is partly due to the fact that more modern hybrids have been bred to withstand higher temperatures as well as poor growing conditions related to extended cool, rainy periods.

Flower drop in tomato plants is caused by stressors. What typically creates stress for a tomato plant can be lack of light, insufficient space between plants, lack of water, extreme temperatures, excess nitrogen, and poor pollination.

Spacing

One factor that limits tomato fruit set is improper spacing. If tomatoes are planted too close together, they will produce fewer fruits and are more susceptible to common tomato diseases. In fact, fungal diseases, like botrytis, can actually cause blooms to drop and result in no fruit. Tomato plants should be spaced between 24 and 36 inches (60-90 cm) apart.

Not Enough Light

Tomatoes need at least 8 hours of sun per day, although in really hot regions they can be grown in dappled shade. In a region with average highs, tomatoes thrive in full sun for 12-16 hours per day.

Tomatoes are “day neutral,” which means plants flower and fruit continuously when temperatures are moderate. Experts at Oregon State University say that, “They flower regardless of day length, but flower earlier and more profusely with long days.” With insufficient daylight the tomato will display blossom drop, but under those conditions probably won’t bloom at all.

Not Enough Water

Tomatoes require plenty of water -- around an inch to 1.5 inches (2.5 to 4 cm) per week. This, of course, may vary according to weather conditions. Plants grown in raised beds or containers will likely need more irrigation. Lack of water results in drought stress which in turn results in abortive blossoming and no fruit.

Stick your finger down into the soil an inch (2.5 cm) or so to determine if the soil is dry. Don’t wait until the plants wilt to water them. Use a soaker hose or drip irrigation and water at the base of the plant early in the morning to give any wet leaves time to dry, thus reducing the incidence of disease. Never water tomatoes from above with a hose or sprinkler.

Too Much Nitrogen

Phosphorus and potassium are both necessary for fruit production. Nitrogen-rich fertilizer can result in beautiful rampant green foliage production and a delay or decrease in flower production.

In order to know how much to fertilize your tomato, take a soil test every 3 years. This will help to determine if the soil needs to be amended or supplemental fertilizer applied. If the results show a lack of nutrients, fertilize BEFORE you plant, and then not again until the first fruit set.

After the first fruit set appears, side dress your plants with 1.5 tablespoons (22 ml) of a complete fertilizer worked into the soil every 2 weeks. Keep in mind that sandy soils will need fertilizer more often than heavy, clay soil.

Extreme Temperatures

If your tomatoes seem to be in good health other than dropping their flowers, they might be suffering from blossom drop, a condition related to weather. Tomato plants require warm temperatures to flourish: 65 to 70 F (18-21 C) during the day, and at least 55 (13 C) at night in order to set fruit. However, if the temperature rises too much (above 85 F (29 C), they will fail to bloom and will not produce fruit. A long term temperature hike can be a problem, but if it only lasts for a week or less, the tomatoes should be okay and resume flowering and setting fruit.

If you have plenty of big blooms but no tomatoes, it may be too cold and wet, or too hot and dry. The resulting blossom drop will make it much more difficult for plants to produce fruit.

Poor Pollination

Weather can also affect pollination. Cold, windy, or wet weather limits the amount of bee activity, which helps pollination and encourages fruits to set. Without pollinators, you will have only a few tomatoes. Once weather returns to normal, however, this should right itself, or you can hand pollinate your tomatoes instead.

While new blooms open every day, they are only receptive to pollination during their first 50 hours. If temperatures drop below 55 F (13 C) at night or reach over 85 F (29 C) during the day, the bees won’t visit or pollinate. When the 50 hour window passes without pollination, the bloom will drop.

You don’t need two plants in order to produce fruit —this is a popular misconception. Tomatoes are often pollinated by bees but they can also be pollinated by the wind or even by your own movements in the garden.

How to Fix Blossom Drop in Tomatoes

• Keep your tomato plants consistently watered, sufficiently fertilized, and overall healthy. Control any stressors such as disease or pests.
• If heat is an issue in your area, plant heat-set varieties the next year. Heat-set, hot-set or heat tolerant varieties include Bella Rosa, Phoenix, Red Bounty, and Tribune. You may also try growing early maturing varieties such as Early Girl.
• Try using a shade filtering cloth spread over tomato stakes to provide some shade during scorching afternoons.
• Encourage the presence of pollinators, and/or hand pollinate by transferring pollen from the anther of a male bloom to the stigma or a female bloom. Avoid using insecticides if possible. If you must use them, spray near dusk when blooms have closed until morning.

Looking for additional tips on growing perfect tomatoes? Download our FREE Tomato Growing Guide and learn how to grow delicious tomatoes.

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