Covering roses for the winter: at what temperature does the robot operate?

All roses grown in temperate climates need to be prepared for winter. This is essential, as many varieties of roses freeze to death in cold, low-snow winters. To prevent bush death, it's important to determine the appropriate temperature to cover roses for the winter, as over-insulating them too early often causes them to wilt.

When roses are covered

Winters in the temperate zone are frosty, and roses can't always survive this period without additional protection. Even though many cultivars can bloom until the autumn frosts, these varieties cannot prepare themselves for a significant drop in temperature. Preparing ornamental flowering plants for winter begins in early autumn, with the soil under the bushes loosened. By the end of September, all buds are removed, signaling the end of the rose's growing season.

The exact time to cover a rose before winter depends on the region's climate and the specific plant variety. Besides the appropriate time, the region also determines the type of cover needed. In some climate zones, roses don't require cover, while in other regions, extensive insulation is necessary.

1. In the central zone of the middle zone, work on insulating roses begins approximately at the end of October, the first ten days of November.
2. In the southern regions, roses don't require significant insulation; minor preparation for winter begins in November.
3. Moscow region The climate in this zone is unstable, so the grower must be prepared to quickly cover the rose starting in mid-September. However, the plant is often covered in mid- to late October.
4. Volgograd – crop preparation for winter begins around the first ten days of November. The process is completed by mid-December.
5. Siberia – early insulation of bushes often leads to the death of the plant. Since snowfall in the Siberian region is heavy, the primary task for gardeners is to provide shelter for the plant before sufficient precipitation has fallen.
6. Ural region – preparation of rose bushes for winter should begin in the last ten days of October, as temperatures in this region drop early. It's also important to consider that snow cover is not always sufficient, and temperatures in the Ural region drop significantly.

Ornamental flowering plants are fully covered only after temperatures drop steadily below freezing, which roses cannot survive without additional insulation. Precisely predicting when such temperatures will occur is virtually impossible. However, a grower can roughly estimate the period during which, if covered, the rose will survive the winter.

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Temperature – when shelter is not yet needed and when it needs to be erected

The plant can easily withstand slight temperature drops. Frosts down to -5°C pose no threat to the plant. At this temperature, the plant thrives and even benefits—a light frost hardens the plant and promotes bush development. For this reason, it's not recommended to cover the plant until the end of October. Even for delicate hybrid tea roses, winter shelter is not recommended until temperatures drop significantly.

Ornamental flowering plants can withstand temperatures down to -7°C without catastrophic consequences. Some growers even recommend waiting until the thermometer reaches this level. Low temperatures help plants properly enter dormancy and also boost their immunity by hardening off the root system and above-ground parts of the plant.

The appropriate temperature for insulating roses is determined by maintaining dryness inside the overwintering structure. Covering the bushes with wet soil, damp leaf litter, or damp covering materials is prohibited. The plant's bushes must also be kept dry. Following this rule reduces the likelihood of harmful insects, rot, and other diseases.

Light cover

This type of insulating structure for overwintering flower bushes is constructed when the winter season in the region is not particularly harsh. This structure is often installed after the roses' hardening-off period, when the air temperature has dropped to -7°C but has not yet reached a stable -10°C or lower. In this case, roses can be covered with the following materials:

• mulch;
• sawdust;
• spruce branches;
• straw;
• foliage.

With a light covering option, the ornamental foliage plant is not completely covered. This type of insulation can also be used in regions where a thick layer of snow covers the winter, effectively protecting the delicate plant from the harmful effects of low temperatures.Siberian region and the like). And in the southern regions, there's no need to cover them for the winter at all, since temperatures in these regions rarely stay at -10°C or below for long.

Capital

Permanent insulation is installed after frosts become stable. In temperate and northern regions, this often occurs in late November or early December. A thick layer of mulch is poured at the base of the bush, topped with spruce branches or other similar material. Then, 3-8 stakes are driven around the perimeter to allow for covering the bush with non-woven material.

A wind-resistant film should be secured over the non-woven fabric. However, wrapping the plant tightly with film is not recommended, as during winter thaws, the material should be lifted on one side to allow air to pass through. This will also prevent the rose from rotting due to rising temperatures under the cover.

The right ways to cover roses

In mid- to late fall, after watering and pruning, the root system of ornamental flowering plants should be properly earthed up. A thick layer of soil should be present above the rhizomes. Afterward, cover the roses with sawdust, dry leaves, or grass. Make sure there are no diseased plant parts or damp mulch under the winter cover. To prevent rot, remove all foliage from the above-ground portions of the bush.

Type of shelter The temperature is determined by the thermometer reading—when the temperature drops to -40°C, the flower needs to be provided with substantial cover. As a preparation, before covering the bushes with insulating material, the plant stems are bent toward the ground and secured in place with specialized hooks. Alternatively, the shoots may not need to be bent; they can be cut close to the ground. Experienced growers believe that there are three winter insulation designs that are superior to others:

• frame version;
• embankment and fence;
• covering roses with lutrasil.

Frame option

A rose bush shelter can be constructed using several metal strips or rods. In addition to metal, plastic sheets, wicker baskets, large plastic pots, wooden pallets, planks, and similar materials can be used for the frame. Arches are made from metal, the ends of which are sunk into the soil around the plant. The shelter construction process involves the following steps:

1. A place is marked around the bent or cut rose.
2. The grower forms a dome of 2 plates over the bush.
3. During harsh winters, a non-woven covering material is placed over the dome, and the rose is additionally sprinkled with fallen leaves or pine needles.
4. The edges of the insulating material are pressed against the ground with bricks on all sides - this will allow you to raise the corner if necessary and ventilate the plant.

It's best to attach the insulating material to the frame after frost and stable low temperatures persist for at least a week or six weeks. A frame is convenient for large rose plantings. Depending on the plant's size, two types of shelters can be constructed: a conical frame for low-growing varieties and pyramidal/spherical shapes for bush varieties.

Fence with embankment

This option involves dry-filling the bush according to a shape determined by the grower. Stainless steel mesh, cardboard boxes, or thin plywood sheets can be used as enclosing material. A fence made of the selected material is erected to the width and height of the specific plant. Insulating material is poured inside the enclosed area:

• leaf litter;
• sawdust;
• hay and the like.

Lutrasil cocoon

Certain tall, varietal roses, particularly standard roses, are wrapped in insulating material for the winter. The material is wrapped around the crown, and the stem is left on the support. The root zone is insulated by hilling. To insulate the stem portion of the bush, it is wrapped in lutrasil or a similar material. The bottom of the cocoon is tied to prevent frost from penetrating beneath the insulation.

Does the time for covering depend on the variety?

The most frost-hardy roses are species and park roses. Few hybrids are considered cold-hardy. However, even the hardiest roses require preparation and insulation for the winter season, although in temperate climates they are rarely covered. Only in the southernmost regions is it possible to avoid winter protection. However, even there, proper preparation for winter is essential: the rhizomes are earthed up, and pinching and fertilizing are completed in the first ten days of September. In November, the bushes are carefully treated with a plant-based antiseptic.

To avoid risk, experienced gardeners recommend at least partially covering bushes, even in the southern part of the country. And if temperatures are likely to drop to -30°C, flowers should be completely insulated, even if the site contains roses that tolerate subzero temperatures well. Gardeners consider the following varieties to be more cold-hardy than others:

• Munch;
• Jens;
• Pink Grotendorst;
• Scabrosa;
• Ritausma;
• Hansa;
• Adelaide Hootles;
• Golden Celebration.

Hybrid tea, exotic, climbing, and miniature rose varieties are less cold-tolerant. These plants require adequate protection throughout the cold season. These varieties are hilled up for the winter, insulated from above, and often even need to be buried in the soil. For a safe wintering, it's recommended to cover climbing roses with a plastic or roofing felt cover.

Misconceptions

The process of preparing roses for winter is a source of both interest and concern for gardeners. Even experienced growers are often misled and make the same mistakes year after year when preparing their bushes for winter. These misconceptions are not always harmless and often lead to stunted growth, lack of flowering, and sometimes even death.

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The more capital, the better

A bush's primary protection from the cold isn't the insulating material, but the air gap between the plant's shoots and the material. For this reason, the warmest shelter option is a sturdy frame, creating a large, warm air gap, and a layer of snow on top of the structure. However, when the air temperature isn't too low, the insulation becomes hot and humid. Under such circumstances, such a shelter can lead to plant rot, which can ultimately lead to its death.

Phosphorus and potassium are the only things needed for successful wintering.

The plant needs top dressing in autumnHowever, to increase the flower's resilience, roses require not only phosphorus and potassium supplements but also other fertilizers containing calcium, magnesium, and other elements. It's important to ensure that fall fertilizers don't contain nitrogen. Fall fertilizers are merely a supportive measure to boost immunity; roses won't survive severe frosts without protection.

All roses are pruned short for the winter.

Bushes of ornamental flowering crops need pruning This procedure is essential when preparing the plant for winter. However, there are several different lengths: medium, short, and long. The short length rejuvenates the flower but negatively impacts frost resistance. The long length, when repeated annually, leads to reduced flowering intensity. There are certain rules that the grower must follow:

1. Pruning is done on a windless day when there is no precipitation and the air humidity is low.
2. Only prune shoots using a sharp tool—this will minimize damage to the bush. Dull pruning shears can crush the shoot, which can lead to the death of the plant.
3. The shoots are removed only at an acute angle, and the cut is directed towards the center of the bush.
4. The cut site must be located at least 1.5 cm from the outermost bud.
5. The bud that will give rise to new stems should face outward. This will widen and give the rose a fuller appearance. However, when you want the shoots to be vertical and avoid lateral shoots, you should leave the bud facing inward.

Before wintering, flowers need to be hilled up.

Hilling roses for the winter is recommended, but this procedure doesn't always benefit the plant. During thaws, the bush can rot, and during subsequent cold spells, this can lead to bark cracking. Hilling is only necessary for own-root roses grown from cuttings. Only their root system is so vulnerable to frost.

Nurseries often sell plants grafted onto rose hips. These specimens are more frost-resistant and don't require hilling. However, if the root system isn't deeply embedded in the soil and the grafting site is above ground, this procedure is also necessary. Peat, sand, and other dry substrates are used. If the grafting site is buried 4 cm or more below the soil, hilling is of no benefit.

The shoots are elastic and easily bend to the ground.

Plants with thick branches are difficult to bend to the ground. For this reason, it's not recommended to delay this until November. Beginning in late September, gradually bend the shoots so that the stems can reach the ground before frost sets in. Stems are most flexible during warmer days, but become more rigid with the onset of cold weather, increasing the risk of accidentally damaging the shoots during late bending.

Lapnik is the best material

Spruce branches are a good material for covering rose bushes, but obtaining them in sufficient quantities, especially for large rose gardens, is difficult. This poses difficulties for growers: to avoid fines, they must contact the forestry department and inquire about planned felling, request the removal of any remaining branches, and so on. Non-woven material such as spunbond or roofing felt can be used as an equivalent alternative. However, it's best to avoid polyethylene, as this material interferes with moisture exchange and air circulation in the shelter.

The best materials for covering bushes

Commercially available materials and improvised means can be used for insulation. The most readily available commercial material is polyethylene film. This insulation is recommended for those types of insulation that don't tolerate frost well. However, the film should be applied loosely to maintain an air gap. Spunbond, sold in rolls or 10-meter packs, is also used. There are several types:

• agrospan;
• agil;
• lutrasil;
• agrotex;
• agroSUF.

Some gardeners don't buy covering material, but use improvised means. The best options include rags, spruce branches, burlap, fallen leaves, peat, and sand. Wood sawdust can also be used to cover roses for the winter. However, these materials are not ideal for covering roses—they only last for one winter. Furthermore, these improvised materials can be difficult to transport.

Conclusion

Roses are a flowerbed's jewel and a gardener's pride, but they're also somewhat fussy. Bushes often require winter shelter, which must be constructed strictly according to the rules. Depending on the region's climate, the type of shelter must be chosen; if it's too warm, the rose will rot, and if it's too cold, it may die.