Poor pollination can keep your squash from producing. This guide is about zucchini rotting on vine.
Why are my fruit rotting when they get about 2 inches long and yes they are rotting from the flower. I can't understand it. In the past they have been fine. Any suggestions?
By Jack K
Sounds like Blossom End rot. Your soil is lacking calcium. The easiest way is to add crushed egg shells to your soil around your plants. I actually grind my eggs shells in a coffee grinder before adding to my plants. It takes a while to work, but it works wonders.
Why do my Zucchini rot after the blossom drops off? They never get to picking size?
Hardiness Zone: 7b
My zucchini plant is rotting. As soon as I get a zucchini on the plant it rots on the vine. Any suggestions?
Hardiness Zone: 6a
By CUTIE PIE from Hegins, PA
I would like to know why my zucchini plants look great with lots of flowers and fruit but when the zucchini get about 3-4 inches they start to rot or go soft? The first fruit I picked was great but since then they have not been good! Thank you.
Hardiness Zone: 6a
Luigi from Lorain, Ohio
Sounds more like blossom rot. (BER) That is a sign of lack of calcium. A few possible solutions to cure it.
-Egg shells, best added when you place them underneath the plant at planting time; but you could add into the soil whenever to gradually bring up traces of calcium. I grind my egg shells until a fine powder and add to the soil and water.
--Liming the soil with calcium carbonate (crushed limestone). Best in the winter or off season, or before planting.
--There are commercial sprays available (calcium nitrate & calcium chloride) that you can spray on or around the plants themselves during the growing season.
-- Grind up a couple dozen calcium citrate dietary supplements, dissolve it in water and water your plants.
This will affect all the new fruit. (08/21/2008)
I have had poor success with growing Zucchini plants that produce Zucchini. There are ants in blossoms and many stems that do not produce zucchini. Should these stems be removed after blossom falls off? What else needs to be done?
Hardiness Zone: 9a
Carol from Stockton, CA
In Indianapolis last year vine borers killed all my squash type plants. This year I used Nematodes to prevent this again. So far I have harvested more than I did last year and I see no signs of any problems. Moles have also been digging for Japanese beetle grubs so I'm using a trap to catch the beetles. I haven't done anything to the soil about the grubs, yet. I do water every day and they seem to love me for it. (06/25/2007)
By Mark B
I have found that too much water and poor drainage due to heavy clay-like soil can be a real problem for Zucchini plants. I always have good luck growing them except for last summer when we had a torrential rainfall that ruined my Zucchini garden. After the heavy rain, the stems and blossoms were rotting before any decent fruits could be produced. Squash plants in general like fluffy, sandy, moist, but well drained soil. They should be planted in a mound or raised bed so they wont be sitting in water after a heavy rain or watering. If the soil is heavy clay, (like ours is), try soil amendments that help loosen and promote drainage. I throw a bag of sand and a big cube of peat moss over my garden every year and till it right into the soil. This fluffs up the soil and also adds volume to it so adding additional soil for a raised bed is not necessary. Surround this with a wood frame to keep the soil from washing away and you have the perfect bed for Zucchini plants.
I used to plant 2-3 Zucchini seeds into each mound and thin the seedlings to 1 plant per mound, but recently, I've found that buying a partial flat of Zucchini plants from the local garden center is well worth the extra 2 or 3 bucks. You'll have a much earlier harvest, healthier plants, and longer growing season. Sprinkle a ring of slow release vegetable food around each plant when planting. Don't water everyday unless temps get above 90F. The large funnel shaped leaves of the Zucchini plant will channel any water that hits them directly to the base of the plant, and they also shield the soil from the sun, keeping it from drying out too quickly. Do this and you'll have more Zucchini than you'll know what to do with. Good Luck.
Thank you for the tip on cutting the end of the vine to encourage female flower production. I was getting frustrated. I also saw on another site that rotting, mushy Zucchini can be from overuse of pesticides and mosquito spraying. I'm trying organic, but it has its own quirks, too. (04/27/2008)
By Mar Lynn
Forgot to mention: The male blossoms are good eatin'. Put them to some use. Lots of recipes online. (04/27/2008)
By Mar Lynn
I have found in the past when leaves are curling and dying often stem borers are ruining the plant. Look for a sawdust like exudation at the base of the plant stems. That is an indication you are infested. (08/12/2008)
Why does my zucchini rot?
Blossom End Rot is a disease common to Zucchini, which causes the blossom end of the fruit to rot. Per Clemson University, "The main symptom is a dark-colored dry rot of the blossom end of the fruit. Blossom-end rot is caused by a lack of calcium in the developing fruit." So either the plant is not absorbing enough calcium from the soil or the soil doesn't have enough calcium in it to start with. The solution is to get a PH soil test kit and test your soil. If it is lacking calcium, the solution would be to add calcium to your soil. Dolomite lime supplies calcium (Ca) as well as Magnesium (Mg) to your soil. It also increases the microbial activity necessary to break down nitrogen into ammonium for absorption by your plant's roots.
If the test shows the soil is okay, then you can increase nutrient uptake to the roots of the plant by mulching and adding compost or other organic matter to your soil (sheep, poultry, cattle, or pork manure has the best carbon to nitrogen ratio), and by watering well.
What causes yellowing in zucchini?
Yellowing is usually caused by a lack of nitrogen, which can be helped by adding nitrogen-rich compost, or by adding lime, or by adding manure. Many agriculture experts have advised amending soil with lime for nitrogen deficiency. There is an issue with organic fertilizers needing to be broken down by microorganisms in the soil before the plant can absorb the nutrients properly. The nitrogen gets "tied up" in this process and does not get absorbed by your plant quickly enough, so it's often recommended to use an inorganic nitrogen application along with your organic fertilizer. Again, the best solution is to do a soil test so you'll be able to eliminate what it is "not".
If the carbon to nitrogen (C:N) ratio of the organic fertilizer is less than about 20:1, "then microorganisms will obtain adequate nitrogen for their needs and will convert the excess organic nitrogen to ammonium (NH4+). This conversion is called mineralization." Ammonium is a form of nitrogen plants can absorb. Carbon acts like a furnace or energy source to speed this conversion process. Sheep, beef, swine, or poultry manure supplies the necessary ratios; speeds up the microbial process; and gets the nutrients to your plants.
A common practice in vegetable gardening is to broadcast lime and other amendments onto the garden soil and mix it well into the dirt and let it rain on it a number of times before planting your plants. In the old days, people didn't test the soil. They always just added the lime as a rule of thumb (right along with the 10-10-10) and they usually had a gorgeous garden. But you can achieve the same proper soil balance without the chemical fertilizer by using organic fertilizers, such as liquid fish fertilizer, complemented by rich compost and organic matter to speed mineralization.
By Lee H