How to help zucchini if ​​they are rotting

Some novice vegetable gardeners believe that simply planting zucchini in the spring, watering occasionally, and you're ready to harvest delicious fruit. In reality, things aren't quite that way. Zucchini require specific care, and if neglected, the fruit can rot right on the vine.

Why zucchini rots – reasons

As zucchini grows and develops, they produce numerous ovaries. Some of these may fall off over time, which is considered completely normal. The plant produces as many ovaries as it can to provide the nutrients needed to form high-quality fruit.

But it sometimes happens that quite large and nearly formed ovaries suddenly begin to rot right on the bushes. This negative phenomenon cannot be considered normal, and it has its causes.

The main causes of decay are the following:

• neglect of crop rotation;
• excess moisture in the soil;
• too much fertilizer has been added to the soil;
• diseases and pests;
• boron or iodine deficiency;
• lack of lighting;
• soil type not suitable for zucchini;
• unsuitable weather conditions;
• dense plantings.

When we see rotting zucchini fruits in the garden, then most likely this disaster occurred for one of the above reasons.

Incorrect crop rotation

Some gardeners have no idea what crop rotation is or why it's important. Meanwhile, it's a scientifically proven method of alternating crops over time and space.

There are two main reasons why crop rotation is important:

• During the growth process, plants release toxic compounds into the soil;
• pathogens and harmful insects remain in the soil to overwinter.

Thus, by planting the same crop in the same bed for 2-3 years in a row, you create nutritional problems for it and provoke its infestation by pests and diseases.

Excess moisture

If the summer is rainy, young zucchini plants are susceptible to rot. The same thing happens if the crop is overwatered. Overwatering creates a greenhouse effect, which also contributes to fruit rot.

Zucchini rots if left on damp soil. In this case, they can be saved by placing straw or thin pieces of wood underneath them. However, remember that slugs will gather there, so they need to be removed.

Fortunately, not all summer seasons are rainy and characterized by prolonged cold spells.

Excess nutrients in the soil

If the soil is overly fertilized or enriched with mineral fertilizers, this promotes the formation of an overly vigorous bush with large leaves. Sunlight, however, cannot penetrate deep into the bush, creating high humidity, which favors the growth of bacteria and fungi that cause zucchini fruit to rot.

Micronutrient deficiencies: boron and iodine

Squash fruits can rot due to a lack of certain micronutrients in the soil. This typically occurs when nutrients such as boron and iodine are deficient.

To replenish boron deficiency, use boric acid. To prepare a working solution, dilute 1 g of the product in 5 liters of water. Boron deficiency can also be replenished by applying complex fertilizers containing a range of microelements, including boron, to the soil or by foliar spraying.

Iodine deficiency in the soil also has an adverse effect on zucchini. This can also cause zucchini fruit to rot.

Diseases and pests

Fungal diseases such as powdery mildew, white and gray rot, and downy mildew can also cause zucchini to rot.

Powdery mildew causes a white coating and sunken spots to appear on fruits and leaves. The disease attacks young leaves and fruit buds. Powdery mildew progresses with wide temperature fluctuations, such as very cool nights and unbearably hot days, as well as when the crop is watered with cold water.

Excessive nitrogen fertilizer application encourages the development of powdery mildew and other fungal diseases. Conversely, phosphorus and potassium fertilizers increase zucchini's resistance to fungal diseases.

During the growing season, regularly inspect zucchini plants for early-stage fungal diseases to prevent them. Better yet, take preventative measures to prevent zucchini diseases.

Unsuitable weather conditions

A closer look at zucchini reveals that it's a southern, heat-loving crop that doesn't tolerate cold snaps or high humidity well. When there are several cold spells and frequent cold rains during the summer, this inevitably causes the zucchini fruit to rot.

In less-than-optimal conditions, zucchini plants become severely weakened, their immunity weakens, and they are unable to resist insidious diseases. Furthermore, a weakened plant is unable to provide sufficient nutrition for many fruits and therefore sheds some of its fruit.

Due to prolonged cool weather, a lack of pollinating insects may occur. Unpollinated flowers rot and fall from the bush.

Gardeners can't change the weather, but they can still alleviate the situation. During rainy seasons, cover the zucchini beds. This will prevent the flowers from becoming damp and rotting.

Dense plantings

Sometimes the weather is favorable, the zucchini nutrition is well-balanced, but the ovaries continue to rot. In this case, the cause of this negative phenomenon is dense planting.

When adjacent plants in a row are planted too close together, their leaves obscure each other. This results in stagnant, moist air in the plant area, preventing sunlight from penetrating the center of the plant and evaporating excess moisture. This creates a favorable environment for the development of fungal diseases, which can cause zucchini fruit to rot.

If this is the situation in your zucchini beds, you need to break off some of the leaves, getting rid of those that shade the center of the bush first.

Why do zucchini turn yellow and rot so quickly?

Many gardeners, when growing zucchini, encounter the problem of the ovaries rotting almost immediately after flowering. This can occur for the following reasons:

An unpollinated flower can rot.

To attract pollinating insects, it's recommended to grow plants that produce white or yellow fruit. When rainy or cloudy weather persists for extended periods, insect flight is not observed. During this time, artificial pollination of flowers is necessary.

Soil moisture deficiency

If a zucchini plant has many strong leaves, they evaporate a lot of moisture in hot weather, which may not be enough for the plant to thrive. This causes the flowers to die and dry out.

Incorrect watering

Water the zucchini at the roots, avoiding water on the leaves and flowers. Otherwise, excess moisture may accumulate on the flowers, causing the young buds to rot.

Nutritional deficiencies

If zucchini nutrition is not balanced enough, rotting and dropping of young ovaries can also occur. In this case, the situation can be corrected by fertilizing with complex mineral fertilizers.

What to do if zucchini is rotting

If you're following all the correct procedures for growing zucchini, but your squash is still rotting, you need to urgently figure out the cause of this negative phenomenon.

Rotting can occur due to high humidity, insufficient light, a deficiency or excess of fertilizers, diseases, or soil that is unsuitable for zucchini.

At high humidity

If zucchini rot is caused by high humidity, you need to urgently optimize your watering regime. It's best to water in furrows, infrequently but thoroughly. Watering once every eight days, applying 20 liters of water under each plant, is sufficient.

Zucchini roots are quite deep, extending deep into the soil. Therefore, when watering, moisten the soil to a depth of 40 cm. After the soil dries, it's a good idea to loosen it. Loosening the soil breaks down the crust on the surface, allowing the zucchini's root system to breathe.

To address excess soil moisture, you can leave weeds around the zucchini plant for a while and remove them later, once the waterlogging has been corrected. Weeds will consume water to thrive and, ultimately, help alleviate the waterlogging more quickly.

With excess fertilizers

We've already discussed how overfertilization causes zucchini plants to grow excessively, producing numerous leaves that block sunlight from penetrating deep into the plant. This creates a zone of increased humidity in the center of the plant, which promotes the development of various diseases.

1. To combat rot for this reason, remove excess leaves to ensure uniform light exposure to all stems and fruits. Place thin pieces of board or straw under the zucchini to prevent them from coming into contact with damp soil.
2. Remove wilted flowers and fungal-infected plant parts from your zucchini bed promptly to slow the spread of disease.
3. Stop fertilizing zucchini with organic and mineral fertilizers, especially those containing nitrogen.
4. Products such as Topaz and Ridomil provide good results against fungal diseases affecting zucchini. Use them according to the waiting period specified in the instructions.
5. If you don't like working with chemicals, replace them with folk remedies such as:

• garlic or onion infusion;
• infusion of medicinal herbs;
• potassium permanganate.

For illnesses

One of the causes of squash rot is plant diseases. Squash is rarely affected by diseases, but it can sometimes be affected by powdery mildew or white rot.

When affected by these fungal diseases, the leaves and fruits of the crop become covered with a white coating consisting of mycelial threads.

Fungal diseases can be combated using potent chemical preparations, among which the following are considered the most effective:

• Thiovit;
• "Topaz";
• "Ridomil".

Preventing zucchini from rotting

As we all know, prevention is better than cure. Therefore, during the zucchini growing season, it's important to take a number of preventative measures to avoid fruit rot.

The following measures are important:

1. Ventilate the plantings. Promptly remove old lower leaves that touch the soil surface. They are the first to be attacked by fungi. Cut them off with a knife, leaving petioles 4 cm long.
2. A day later, after trimming off excess leaves, you need to spray the bushes with a solution of brilliant green (1 teaspoon per 10 liters of water).
3. Rejuvenation of the bush must be carried out throughout the growing season, thinning the shoots from old leaves, and prolonging the fruiting period.
4. During inclement weather, cover your zucchini plants. A piece of plastic film stretched over stakes or an old umbrella will work well. This will protect the plant from excess moisture while maintaining air circulation.

Tips and recommendations

Below are some tips and recommendations that can help you prevent zucchini from rotting and get a good harvest.

1. Pollination of zucchini plants is poor when the central leaves are closed. To solve this problem, remove several leaves from the plant, leaving the petioles. Sunlight penetrating the center can dry out the powdery mildew mycelium.
2. Removed leaves and rotting fruit from the garden and burn them. This will improve next year's harvest.
3. If you plan to use a chemical against fungal diseases, follow the instructions strictly. Otherwise, leaf burn may occur.
4. Iodine deficiency can be easily replenished by spraying the zucchini leaves with iodine alcohol tincture (30 drops per 10 liters of water).
5. Zucchini should be watered infrequently but thoroughly. Under normal conditions, once a week is sufficient in the summer.
6. Don't forget to loosen the soil. Zucchini roots need oxygen. Mulch the soil with straw or sawdust.
7. During the flowering phase, pollinate by hand. You can use a watercolor brush to transfer pollen from the male flower to the female. It's even better if you have a beehive in your garden.
8. Harmful insects can also ruin the quality of the harvest. Slugs can cause the tips of zucchini to rot. You can repel slugs by planting crops such as:

• mustard;
• lavender;
• garlic;
• hot pepper;
• sage.

When growing zucchini, it's also important to harvest the crop promptly, otherwise the fruit will become overgrown and less tasty. Furthermore, this will allow the plant to divert nutrients to other fruits, increasing the overall zucchini yield. You can effectively combat fungi by sowing disease-resistant hybrid zucchini seeds. By following our recommendations, you'll protect your zucchini from rot and ensure a bountiful harvest.