There are few bigger disappointments in the garden than when your plants don’t produce vegetables or fruit after you’ve tended them all season.
That’s been the case for some Maine growers this year, who are finding that their peppers flowered but never fruited or their tomatoes grew but stayed green.
Plants are complicated, but there are several common reasons why they don’t produce or ripen. You can manage factors to help avoid the same problem in next year’s garden.
Too much fertilizer
You know your plants need nutrients to grow, but if there’s too much nitrogen in the soil, they might produce more leaves instead of fruit. Overfertilization can delay flowers forming and cause those flowers to set fewer fruits.
It can also slow the ripening process for fruits, including tomatoes. Tomatoes in particular need to have enough potassium and deep enough roots to use it.
A soil test can tell you what nutrients you have, what you might want to add and how much. With or without a soil test, pay attention to recommended application rates for fertilizers. Some simple math will break down how much you need for a small area like a home garden.
Pollinator problems
If your plants flowered but never produced fruit, it’s possible that the flowers weren’t pollinated.
Some plants, especially those in the cucurbit family (including melons, pumpkins, squash, zucchini and gourds), have separate male and female flowers. You can tell the female flowers by the small knobby fruit in the vine, behind blossoms. When the pollen is carried between male and female flowers by insects like bees, the plants “reproduce,” creating the pepper or tomato as offspring.
Bees are less active when it rains, so wet weather could delay pollination. Your area may also just have fewer pollinators — native pollinator populations are in decline, even in Maine. Or, if you’re using insecticides and spraying them in the morning, when bees are active, you might be killing your pollinators.
Along with changing your pesticide habits (spraying at dusk means most flowers will be closed), you can plant pollinator-friendly landscape species that flower at different times throughout the season.
You can also pollinate plants yourself by touching the male flowers to the female flowers, or transfer the male pollen to the female flower using a paintbrush.
High or low temperatures
Plants may not set fruit if nighttime temperatures are below 50 degrees Fahrenheit. The same thing can happen if it’s above 95 degrees in the daytime and stays above 75 at night.
High temperatures can also cause flowers to wilt or drop from plants. They’ll start again when the temperature cools, but that means the fruit emerges later, which can make a big difference in a short growing season like Maine’s.
Weather could also be to blame if the fruit appears but is slow to ripen. Tomato ripening slows down noticeably at temperatures above 85 degrees.
Maine saw a record-breaking heat wave in June and another in July this year. Bangor had its second-warmest summer on record. It felt like 95 degrees or more across parts of the state.
Not enough time to grow
Plants that originated in much hotter parts of the world than Maine, particularly peppers, can be tricky to grow here. They need a lot of time to bear fruit, and for the fruit to ripen.
If you started your seeds too late, the plants may not have had time to mature. “Season extenders,” such as hoop houses, are one way to buy more time and get higher temperatures using the sun’s energy. Mulching the beds or using dark landscape fabric keeps more heat in the soil.
How to get tomatoes to ripen
It’s too late for plants that never flowered. But if you’re waiting for your tomatoes to turn (or if nighttime temperatures are dropping below 50 degrees in your area), try picking them once they show a little bit of red and keeping them inside to ripen.
The plant can then focus its energy on any remaining fruits that are still fully green. Pinch off any remaining flowers at this point for the same reason.
Peppers should ripen indoors at room temperature once you pick them; some growers even cut the entire vine and bring it in.
