Why melons don’t set and they have empty flowers, reasons and what to do

The variety of melon varieties with different ripening periods and the possibility of growing them throughout the Russian Federation are attractive. Good harvests are grown not only in the North Caucasus and Lower Volga regions. There are varieties bred specifically for the Altai Territory, regions of Western and Eastern Siberia. With the right agricultural technology, farmers and amateur vegetable growers receive good harvests in all weather conditions.

Reference.Scientists have proven that it is more profitable grow melons in a greenhouse. Higher productivity and profitability.

Melons are grown in melon fields or in a greenhouse by direct sowing of seeds in the ground and by seedlings. Strong vines and active flowering do not always guarantee a future harvest. There are many reasons why melons do not set. Having studied the nature and characteristics of this light- and heat-loving plant, you can force it to form fruits without much effort.

What does a melon look like during the flowering period?

Male flowers appear first on a zero-order shoot. In early ripening varieties they open in the axils of 2–3 leaves, in late varieties - after 4–5 leaves. In total, you can count from 6 to 30 male flowers on a bush, but not a single female flower can be found. If the female flower has formed on the main shoot, it will most likely be sterile and will not form a fruit.

Productive female flowers open on shoots of the 2nd–3rd order; it is from these that the fruits are formed. Their flowering can last for 30 days. List of unfavorable factors affecting the number of female flowers and the speed of their flowering:

• shading;
• incorrect watering scheme (excess, lack of moisture);
• lack of fertilizing or improper use of fertilizers.

The buds begin to open early in the morning (6 o'clock), at noon all the pollen from the male flowers falls out and they wither, while the unpollinated female flowers continue to bloom for 1–2 days. Let's look at all the reasons for poor pollination.

What doesn't melon like?

Melon can be called a finicky plant, because the list of what it doesn’t like is quite long:

• low temperature;
• high humidity;
• bright sun rays;
• draft;
• weeds;
• heavy soil;
• acidic soils.

Wet air

Bad weather for the crop is rain and a sharp drop in air temperature to 15 °C and below. Plants planted in a greenhouse are easy to help. Air humidity can be regulated by periodic ventilation, the plantings can be covered with covering material at night, or the heating system can be turned on.

When growing crops in open ground, it is more difficult to regulate humidity, but it is also possible. During prolonged rains, you can place plastic arches on the ridge and stretch PVC film over them. This will relieve the plants from excess dampness and help save the ovaries. The film should be opened slightly at the ends during the day, as stagnant air can provoke fungal diseases and impair pollination.

Watering with cold water

Your plants will be susceptible to root rot and other diseases caused by fungal infections if you over-water them during the formation of ovaries. The crop needs moisture during the initial growth period.

At this time, you need to carefully monitor the temperature of the irrigation water. On cool days, the lower temperature limit is 20 °C; on hot days it can be higher, the upper limit is 40 °C. Any plant is more comfortable if the water temperature for irrigation is close to the air temperature, but does not exceed the lower limit (15 °C).

Cold drafts

Drafts are dangerous for ovaries in a greenhouse, but even when planting melon plants in open ground, they can negatively affect the development and pollination of the melon crop. When choosing a place for planting, take into account the wind rose and plant seeds (seedlings) in places protected from the north wind.

Any polycarbonate greenhouse must have a properly organized ventilation system. It includes: windows, doors. It is more convenient if the windows are embedded in the ceiling.If they are built into doors, then when ventilating they are always opened on one side, this helps to avoid drafts.

Acidic soils

Melon grows well on light soil: loamy, sandy loam. This culture does not like acidic soil that does not conduct air well and retain moisture. In heavy soil with a high clay content, add river sand - ½ bucket per square meter.

Soddy-podzolic soils become deoxidized. For this, different technologies are used:

• apply lime to the predecessor crop (root crops, cabbage);
• lime in the fall;
• add chalk and dolomite flour to the soil for digging in the spring (2 weeks before planting melons).

In acidic soil, melons develop more slowly, get sick more often, form few ovaries, and the fruits are smaller in size and have low sugar content.

Concentrated fertilizers

By tradition, many vegetable growers fertilize after planting any seedlings and, in the first half of summer, focus on fertilizers containing nitrogen. When growing melons, fertilizers containing nitrogen should be used with caution. Nitrogen stimulates the growth of shoots and leaves, but slows down the formation of ovaries. Bushes overfed with nitrogen are more likely to get sick, and the fruits may contain nitrates.

It is better to apply fertilizers to the holes when planting:

• humus 1 liter;
• ¼ cup of ash;
• 1 tsp. the drug Zdraven-turbo.

After the ovaries have appeared on the bushes, you only need to fertilize 2 times with an infusion of grass with the addition of potassium monophosphate (10 g per bucket). For feeding, dilute the infusion with water in a ratio of 1:5.  

Fighting methods

Experienced vegetable growers begin to form melon bushes after 4 leaves appear on the central shoot.By pinching the growth point, they stimulate the appearance of new shoots of the 2nd order, which appear from the axils left on the stem of the leaves.

Another proven way to combat barren flowers and a small number of ovaries on melons is to purchase seeds that are 2-3 years old. Bushes with empty flowers most often grow from last year's seeds.

Why don't melons set?

When growing melon in a winter greenhouse, a situation where the plant blooms but there are no ovaries occurs due to insufficient lighting. With a lack of light, the interval between the beginning of the formation of male and female buds increases. Normally this is 3–5 days, but if there is a lack of sunlight it can take up to 30 days.

If the plant is not formed, the bushes will not send out side shoots in time. This is a common reason why melons have no ovaries. The probability of barren flowers appearing on shoots of the 2nd order is high, so the lower two shoots are removed, only the top 2 are left, they also need to be pinched over the 5th leaf. When ovaries of the 3rd order begin to form on shoots, the crop is normalized - no more than 3-4 formed ovaries are left on each bush. One lash - one ovary.

What to do if a melon has a barren flower?

Despite proper care, the bushes have barren flowers. What to do in this case? Situations are different. On some bushes there are only male flowers with stamens, on others there are only female flowers with pistils, on others there are both, but there are no ovaries.

Important! With short days and high air temperatures, more female flowers are produced.

If there are only female buds on the bushes, and the male ones have already withered or for some reason have not formed, you cannot do without artificial pollination. Let's look at how to pollinate a melon with your own hands below.Pollen for pollination can be taken from other melon plants, for example, from zucchini.

Another reason for barren flowers is the lack of pollinating insects, if the entire bush is covered with flowers, but there is not a single ovary on the melons. In this case, only artificial pollination will save you.

Why are there no female flowers on melon?

The most common reason is the absence of shoots of the 2nd and 3rd order. To bear fruit, melon needs shoots of the 3rd order; it is on them that female flowers are formed. For them to form, pinch the central stem and shoots of the 2nd order above the 4th leaf.

Falling ovaries on melon

Melon ovaries fall off for various reasons, but the result is the same - low yield or its complete absence. Gardeners' opinions why did the ovaries on their melons fall off?:

• during flowering it was hot, the air was dry, this interfered with pollination;
• hot weather worsens the nutrition of the fruits and they fall off;
• insufficient watering during flowering;
• thickened planting;
• lack of lighting;
• sharp daily temperature fluctuations;
• depleted soil and lack of fertilizing.

These are real opinions of amateur vegetable growers who have encountered the problem of ovaries falling off on melons.

Artificial pollination of melon

It is not difficult to master the process of pollinating melon by hand. First you need to learn to distinguish the sex of a flower. A male flower has 5 stamens, while a female flower has a pistil and an embryo of the future fruit.

Pollen retains its ability until the middle of the day, so artificial pollination should be carried out in the first half of the day, or preferably early in the morning. Select the largest male flowers, bend the petals and walk with them over the female buds, touching the stamens to the area where the pistil is located.