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Gardening Answers Knowledgebase

Plant Answer Line Question

Keywords: Tomatoes--Care and maintenance

I purchased an heirloom tomato at Home Depot (I know) and planted it deep in a pot in about the middle of June. I put the pot in a very sunny spot, I have fed it twice and watered it daily. It grew like crazy, then slowed when it began to show fruit. Now it is full of fruit but nothing wants to ripen. I removed a tomato today that had split.

Is there anything I can do to help the tomatoes ripen?


A few suggestions:
--Do not fertilize the plants any more, as this mostly stimulates growth rather than fruit ripening.
--You can drape clear plastic over the plant to keep the temperature up, especially at night, just make sure to remove it during the hottest days so you do not cook the plants.
--Stressing the plant by cutting the roots with a spade 8-12 inches from the stem will encourage ripening. Underwatering will also stress the plant.
--Remove any flowers and really small fruit that probably will not ripen anyway to encourage the plant's energy towards the developed fruit.
--If you still end up with green tomatoes, bring them inside before the first frost, they may ripen on the windowsill.

Also available in many bookstores or libraries (including the Miller Library) is Growing Vegetables West of the Cascades, by Steve Solomon

Date 2017-12-09
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Plant Answer Line Question

Keywords: Tomatoes--Care and maintenance, Lycopersicon, Tomatoes--Diseases and pests

It's midsummer, and I have a bunch of healthy-looking green tomato plants without any fruit. Shortly after I planted the starts, the flowers developed, and promptly fell off, taking a bit of the stem-end with them. The spot where I've planted them is in full sun, they have good soil, and they get watered as they should. Any idea what might be going wrong?


The problem which most closely resembles your description of what is happening with your tomato plants (flowers falling off shortly after planting, and taking a bit of the stem as they drop) is called 'blossom drop.' According to D. G. Hessayon's Vegetable Expert (PBI, 1990), blossom drop occurs when pollination fails to take place, and there is dryness at the roots or in the air. There is no treatment for this malady, but watering regularly, spraying flowers in the morning, and tapping the plants to aid pollination are preventive measures. Attracting beneficial insects to your garden will also help with pollination.

Here are links to more information that may be useful to you:

  • University of California Integrated Pest Management pages on tomato problems and pollination
  • Washington State University - Spokane County Extension: Why Blossoms Fail. Note also that WSU Extension in Spokane County says cool night temperatures may cause blossom drop.
  • University of Illinois Extension: "Tomato blossom drop is very common with high summer temperatures. Tomatoes will drop blossoms when daytime temperatures in the summer are above 90 degrees F. Blossoms will also drop earlier in the growing season when night temperatures drop below 55 degrees F."
  • This article from about.com provides a lot of detail about the problem and how to prevent it:
    Blossom drop can be attributed to several causes, most often related to either temperature and/or stress.
    1. Temperature too high or too low
    2. Lack of pollination
    3. Nitrogen: too much or too little
    4. Humidity too high or low humidity
    5. Lack of water
    6. Stress from insect damage or disease
    7. Too heavy fruit set

    This article recommends planting varieties known to do well in your climate, ensuring pollination, avoiding over-fertilizing, taking note of humidity levels, and watering deeply once a week in dry weather.

Date 2017-04-19
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Garden Tip

Keywords: Tomatoes--Care and maintenance, Tomatoes

Whether you planted your tomatoes in April or mid-June, by mid-summer it's time to think about training and staking strategies. An eight-inch tomato may be dwarfed by a "tomato cage" in June, but by September the cage is usually swallowed up and listing dangerously to one side. The alternative, tying up one central branch to a stake, improves disease resistance, but requires constant vigilance to pinch out all suckers. University of the Virgin Islands provides an excellent illustrated explanation on training tomatoes.

Date: 2007-06-07
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Garden Tip

Keywords: Tomatoes--Care and maintenance, Lycopersicon

When, exactly, is the best time to harvest a tomato for perfect flavor? According to expert Lois Hole, "tomatoes have the best flavor when picked just before they've reached their color peak." If left on the vine until soft sugar and acid will decrease, degrading the flavor. The wonderful little book called Lois Hole's Tomato Favorites (Lone Pine, $12.95) is filled with growing information, recipes, facts and folklore with color pictures and quick reference charts.

Date: 2007-05-17
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August 01 2017 12:36:01