Why Are My Tomatoes Not Bearing?

As each flower fades, one fruit develops in that same spot.


Yellow, star-shaped tomato flowers (Lycopersicon esculentum) may look like an ornamental preview of the main act but, in fact, they directly determine fruit production. Poor flowering and premature flower drop prevent tomato plants from setting fruit, but you can usually reverse the problem with proper care. Tomatoes grow year-round in U.S. Department of Agriculture plant hardiness zones 10 through 11, or as a warm-season annual in all other climate zones.

Flowering and Nutrient Deficiency

Tomato plants that don't flower at all but look otherwise healthy with lush foliage and strong growth suffer from imbalanced nutrients, specifically too much nitrogen and not enough phosphate. Feed the tomatoes using a balanced 10-10-10 or 20-20-20 fertilizer, or use specialized tomato fertilizer. Apply twice a month by mixing 1 tablespoon of water-soluble plant food in 1 gallon of water. Pour the diluted fertilizer onto the soil around each plant using a full gallon per plant.

Flowering and Light Deficiency

Without enough sunlight, tomatoes fail to flower or flower sporadically, but too much sun also diminishes flowering and fruit set. Grow tomatoes in a spot that regularly gets a minimum of six hours and up to eight to 10 hours of direct sun per day in cool coastal areas where fog cover is common. In hot growing regions, plant tomatoes where they get morning sun and dappled afternoon shade.

Flowers Falling Prematurely

Excessively cool or warm temperatures cause tomato flowers to fall prematurely. Tomatoes flower and set fruit when nighttime temperatures are above 55 degrees Fahrenheit and below 70 F and daytime temperatures are around 85 F. Low or high temperatures prevent pollen from developing properly, causing the flower drop before fruit sets. Though flower drop looks alarming, tomatoes commonly start flowering again when the temperatures either warm up or cool down.

Pollination and Fruit Set

Pollination precedes fruit production. Fortunately, each tomato flower is self-fertile, containing both pollen and stigma. Outdoors, wind and insects usually shake the flowers enough to transfer pollen within the blooms, but in still weather or when pollinators are absent, you can help nature out by gently shaking the plants. Choose a sunny dry day when the flowers are fully open to pollinate. In a greenhouse growing environment, set up a fan to help distribute pollen.

Flower Drop and Moisture Deficiency

When tomato flowers shrivel up and die before opening fully, the plants need more water. Water them every few days to once a week during the summer with 2 inches of water in total per week. Use a slow-drip system at the base of the stalks to thoroughly wet the soil. Avoid getting the flowers wet during watering or you could wash off the pollen. Water containers every day, or even twice a day during hot weather. Feel the soil in the container and water when it starts to dry out.

About the Author


Photo Credits

  • Lusyaya/iStock/Getty Images
Suggest a Correction