How to plant cucumber seedlings in a greenhouse: features and rules

In the Moscow region and other areas where summers are short and unpredictable, greenhouses are very popular among gardeners for growing heat-loving vegetables, including cucumbers. Although an abundance of fruit can only be achieved with proper daily care and careful selection of varieties, achieving a good harvest in late spring and early summer is only possible in greenhouse conditions.

Selecting a variety

Not all cucumber varieties are suitable for planting in a greenhouse; only self-pollinating varieties or those that don't require pollination at all are suitable. Examples include the following:

1. Suomi F ripens in 38 days from germination. It produces dark green, striped, pimply fruits, 4 to 6 cm long.
2. Orpheus has a growing season of 36 to 38 days. Its 12 cm long fruits have small tubercles.
3. Romance with a long fruiting period, has dark green fruits with white hairs on them.
4. Emerald with early ripening fruits 16 cm long.
5. Alex gherkins, which allow you to get up to 25 kg of harvest from one m².

Some hybrid varieties from Holland are also popular, as these plants begin producing abundant fruit consistently within two months of planting. They are beautiful and delicious, and resistant to pests and diseases. With proper care, a single plant can yield up to 25 kg of cucumbers.

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You can calculate the time to plant cucumber seedlings in a greenhouse based on the desired harvest date. If you want to grow cucumbers outside of summer, the greenhouse must be heated and able to maintain a temperature of 20 to 25°C and humidity of 70 to 80%.

Preparatory work

Cucumber seedlings can only be planted in a pre-prepared greenhouse. For unheated greenhouses, preparations should be made in the fall or early spring. The latest time to plant cucumbers is two months before transplanting.

They begin by clearing the premises of:

• trellis;
• inventory;
• last year's leftovers.

All interior surfaces should be thoroughly washed with detergent. Then, the greenhouse should be thoroughly ventilated and dried. All cracks should be sealed with sealant, and any broken components should be replaced.

The internal surfaces prepared in this way should be disinfected taking into account the material from which the structure is made:

1. The wooden parts of the greenhouse must first be treated with bleach, then soaked in copper sulfate, and only then whitewashed.
2. If the parts are made of metal, they must be washed with vinegar, tidied up and painted, and then washed with Bordeaux mixture.
3. All glass parts are thoroughly washed with potassium permanganate.

To properly plant the seedlings, you need to prepare the soil. First, add manure to the greenhouse or hotbed. A couple of weeks before transplanting the cucumber seedlings, prepare the soil. This is done as follows:

1. Place the manure in stacks three meters wide and one and a half meters high, make holes in it and pour boiling water over it, mix thoroughly.
2. After all layers of manure have warmed up, it is distributed along the walls throughout the greenhouse.
3. After four days, the manure will settle; you need to sprinkle it with a 3 mm layer of wood ash, and add soil on top.

All these measures will allow gardeners to protect greenhouse plants from fungi, bacteria, insects, and their larvae. Seedling preparation begins a month before transplanting cucumbers into the greenhouse. To do this, sow these vegetables in:

• wooden boxes;
• peat pots or cups;
• sods.

With the first method, a mixture of turf soil and humus in a ratio of 2:1 is placed in boxes 50 cm long, 30 cm wide and 70 cm deep.

In the second case, before planting the seedlings, add a nutrient mixture enriched with 8 g of ammonium nitrate, 12 g of superphosphate, and 5 g of potassium salt to the pots. Then, plant the cucumber seeds in the pots.

In the third case, turf is used. To do this, cut 8 cm long, 7 cm deep, and 7 cm wide pieces from the top layer of the beds where legumes or cereals were grown. These are then turned over so that the grass is on the bottom, and the seeds are planted in the pits and covered with soil.

In the second and third cases, only sprouted seeds are used. They can be germinated in a napkin or sawdust, and when one or two true leaves appear, the cucumber seedlings are transplanted into a pot or sod. Once the plant stems are strong enough and have tendrils and 5-6 true leaves, it's time to plant the cucumbers in a greenhouse.

Planting diagram

When choosing a planting pattern, consider the size of the greenhouse or hothouse, its design, and growing conditions. There are several types of seedling planting:

• wide-row;
• tape;
• the usual way.

When planting in wide rows, maintain a distance of 1 meter between rows of seedlings and 30 cm between seedlings. If using the ribbon planting method, space rows 80 cm apart. With the standard planting method, space rows 60 to 70 cm apart.

When it's time to plant cucumber seedlings in the greenhouse, dig holes 30 to 40 cm apart, water them with a warm, weak solution of potassium permanganate, and plant the seedlings. Place the roots close to the soil surface. Then compact the planting site lightly, add soil, and mulch.

When transplanting cucumbers, be especially careful with the plant's roots, as they are very fragile. Therefore, the seedling should not be removed from the soil but rather placed into the garden bed along with it.

Types of planting

The best way to plant cucumbers in a greenhouse is in peat pots. They should be staggered, seven plants per bed, watered with room-temperature water, and covered with plastic wrap stretched over arches. The next watering should be done a week after planting. After another 14 days, remove the plastic wrap and fertilize with cow manure diluted in water at a ratio of 1:20.

To grow cucumbers faster in an unheated room or outdoors, you can use "warm" beds. To do this, two weeks before planting, you need to:

• make trenches;
• put manure in them;
• pour hot water;
• cover with cellophane.

A week later, the trenches are filled with compost and covered with nutrient-rich soil. Water again and cover with plastic wrap. After another week, cucumbers can be planted.

These vegetables can also be grown in small containers. This method is called potting. A paper cup or half an eggshell is used as a container. These cups are filled with a 3:1 mixture of peat and sawdust, with the addition of vermicompost. Before transplanting the plants into the greenhouse, the cup or eggshell is pressed down, and after planting, the cup or eggshell is watered generously and mulched with compost or soil.

You can significantly reduce the time it takes cucumbers to emerge by growing them in so-called jars—namely, five-liter plastic bottles with the bottom and top cut off. They should be buried 5 cm deep in the garden bed, filled with fertile soil, and a trellis installed nearby. Once the soil warms up, the vegetables can be transplanted into them.

When the greenhouse is small, the "pie" method is used for planting cucumbers:

1. It is prepared from dried potato peelings, passed through a meat grinder and soaked in water.
2. Before planting cucumbers, you need to make holes in the soil and pour half of the mixture into them.
3. Sprinkle soil on top, then pour in the remaining mixture and sprinkle with soil again.

Caring for seedlings

It's important to properly care for seedlings transplanted into the ground: monitor the bush's development, remove damaged shoots, protect against pests and diseases, water and fertilize promptly, and maintain the correct air temperature. When using a trellis, vines are tied to it after eight leaves emerge.

It is not recommended to plant cucumbers in the same greenhouse with:

• tomatoes;
• pepper.

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To ensure a good harvest, strengthen the immune system, and extend the fruiting period, cucumbers need to be fed. Both chemical and organic fertilizers can be used. However, it is recommended for:

• For the first feeding, use a complex mineral fertilizer;
• the second one is divorced manure;
• then complex fertilizer again;
• After fruiting begins, the plants are fed with manure once every two weeks.

Water cucumbers morning and evening, using only warm water at a rate of up to 10 liters per square meter. On hot days, water three times a week, and on cloudy days, once or twice. In addition, during hot weather, mist them with warm water, ensuring that drops fall on the leaves.

It's a good idea to loosen the soil after watering, preventing plant roots from appearing above. A good indicator of a favorable greenhouse climate is the plant's leaves. If they turn white, they should be removed and the greenhouse disinfected.

If it gets too wet, the cucumber roots can rot. This will negatively impact the shoots and leaves. In this case, the greenhouse needs to be ventilated and kept warm, but not too hot. Cucumbers love warmth, but they don't tolerate heat or cold. Therefore, the most serious temperature problems are related to:

• decrease in spring and at night;
• rising on a hot summer afternoon.

To combat cold during frosts, use a heater. If that's not available, the seedlings can be covered overnight with two layers of covering material, or each plant can be covered with a plastic bottle with the bottom cut off. To combat heat, shading the top of the greenhouse with whitewash and watering the paths with cold water helps. You can also set up several containers of cold water.

Growing cucumbers requires managing diseases and pests. Much depends on proper care, but weather conditions can also hinder the successful cultivation of this vegetable. If the greenhouse is too hot or damp, this can lead to rot. A good remedy is a mixture of lime and ash in a 1:3 ratio, sprinkled on the stems and then planted.

The best way to combat aphids is to use ash:

• a glass of ash is poured into a bucket of hot water;
• the next day, add a tablespoon of grated laundry soap;
• the resulting solution is sprayed on the plant;
• The procedure is repeated once a week.

But the best remedy for illness is boosting immunity. To do this, spray the plant with iodine diluted in water at a ratio of 35:1.

Here are some typical mistakes gardeners make:

1. Some inexperienced vegetable growers believe that the older the seedlings, the better they will take to transplanting. In fact, even at one month of age, seedlings take longer to establish themselves in their new location and are prone to rot. When transplanted at this age or older, fruiting is delayed.
2. To harvest more fruit, many people plant their seedlings too close together. This is a mistake. The vines branch poorly, and few cucumbers grow. Furthermore, ventilation is impaired, the cucumbers receive insufficient light, and care becomes more difficult: you might miss the appearance of pests or signs of incipient disease.
3. Applying large amounts of fertilizer at planting. By doing this, the vegetable grower hopes to avoid subsequent fertilizing of the cucumbers. However, they fail to take into account that plants are unable to absorb large doses of fertilizer.
4. Some people use the same fertilizer for seedlings and adult plants, without taking into account that cucumbers need different nutrients at each stage of development.

If shoots aren't pinched, the lack of proper ventilation can cause ovaries to fall off, and fungal diseases can develop on the vines. If cucumbers with different pollination types are planted in a greenhouse, the resulting cucumbers may be less tasty.

Watering with cold water or planting too closely can cause the formation of empty flowers instead of ovaries. To remedy this, place a barrel of water in the greenhouse, add herbs, and toss in a loaf of old bread. Once the mixture has fermented, strain it and water the plants.

Once cucumbers begin to bear fruit, inspect the plants twice a week and remove any green cucumbers. Different cucumber varieties have different shelf lives. Some are better suited for pickling and canning, while others are better suited for salads. It's best not to plant these varieties close together to avoid spoiling their flavor.

Growing cucumbers in a greenhouse isn't all that difficult, but to ensure a good harvest, it's helpful to thoroughly research the process first, so you can learn from others' mistakes and avoid making your own.