Protecting plants from frost: this is how it works

The first frost will soon be around the corner and some plants now have to be protected. Whether with winter protection tents, frost protection fleece or coconut mats - there are many ways to protect the plants.

Frost can damage plants if they are sensitive. Therefore, caution is advised as soon as the weather report announces icy temperatures overnight. Prepare yourself with our tips on how to protect your garden and plants from frost.

Which plants should you protect from frost?

Not every plant needs to be protected from low temperatures, but frost protection is especially important for sensitive plants. These include, for example:

• Plants in pots and containers, balcony plants
• Young plants, both vegetables and young trees
• Vegetables that are sensitive to frost and should be harvested for longer
• Plants pre-cultivated in the greenhouse that can be bought in the garden center in autumn or spring
• Tropical houseplants
• Fruit trees in spring, as late frost can damage the flowers
• Roses
• Lawn, because some grasses are less hardy than others
• Plants that are assigned a hardiness zone of 6 or higher

tip: When it comes to frost protection, use the hardiness zone in your region and the degree of hardiness of the plant as a guide. The winter hardiness of ornamental plants and other crops is known and is expressed by specifying the winter hardiness zone. This is a geographical area that encompasses a specific range of climatic conditions that are important for the growth and survival of plants. Plants that are assigned a winter hardiness zone of 6 or higher should definitely be protected by us.

At what temperature should you cover plants?

There is no general answer to the question of the temperatures at which plants should be covered. This can only be clarified in connection with the season and the properties of the plant. Plants that are very hardy may never need to be protected from frost. Others, however, are at risk of frost damage between autumn and spring or only in spring. Not every plant is frost-resistant in the same way: You should therefore always adapt your frost protection to the circumstances.

Tip: Plants that you bought in the garden center in spring or autumn and that are actually hardy often fall victim to frosts. On the one hand, they have not yet developed a strong root system and are drying up because the cold air removes moisture from the soil. In addition, the plants are not yet used to the environmental conditions in the field. Due to the warm preculture, they are often particularly sensitive and should also be protected as a precaution.

Protect plants from frost in autumn and winter

The phase in which you should prepare for frost protection begins in autumn. Pay attention to the weather report and temperatures. The first frosts of the season usually appear on clear, windless nights - at the latest then you should take action.

• Plants can dry up in winter too - make sure you water them regularly after the soil has thawed. Avoid waterlogging!
• Evergreen woody plants, roses and warmth-loving woody plants must be protected during prolonged frost and winter sun. Cover the plants only with air-permeable materials, such as frost protection fleece or jute.
• Winter vegetables are not damaged by the cold, but you can still cover the vegetables so that you can continue to harvest without any problems despite the snow.
• When overwintering potted, balcony and container plants, it should be noted that most potted plants are damaged if overwintered too warm. Therefore, find out about the respective plant which winter conditions it needs.
• Cover plants from winter hardiness zone 6.
• To prevent frost drying, the soil can be mulched and watered on frost-free days. Frost drought leads to a lack of water in plants, because the leaves transpire water, but cannot absorb new water through the frozen soil and eventually wither. Flat-rooted species such as rhododendrons are particularly affected. Because their roots do not reach deep into the ground, where there is plant-available water.
• Pile up roses.
• The lawn is protected by providing it with a fertilizer containing potassium in the autumn. Potassium makes the plants more resistant and makes them strong for the cold season. Special autumn fertilizers like ours are suitable for this Plantura organic autumn lawn fertilizer especially good with long-term effects. The nutrients it contains must first be broken down in the soil and made available to the plants. As a result, the grasses are cared for gently and long-term over a period of three months. Perennial plants also benefit from autumn lawn fertilizers, because they can cope better with dry and cold phases.

Protect plants in spring

Plants should be grown in spring until the ice saints (12. to 15. May) must be protected from frost - because until then there is a risk of night frosts.

• Cover your plants until the ice saints at night, for example with frost protection fleece.
• Container and potted plants should only be put out continuously from mid-May. However, they can be put outside during the day beforehand.
• You can also protect the blossoms of fruit trees from late frosts - a good way to do this is to use frost protection candles.
• Keep a close eye on the daily weather forecast. If temperatures are to fall again after warmer periods, it is important to protect the plants from frost.

Tip: Even if spring plants are already being sold in the garden center before the ice saints, they should still be Wait until after this date to plant the beds or the plants until then before frost protection.

Winter protection for plants: these options exist

There are various options and materials to choose from that can be used to protect plants from frost. Did you know that snow is also a natural protection against frost for plants? It has an insulating effect - just like some of the materials that we are now introducing to you.

Winter protection tents for plants

Winter protection tents are plant tents made of foil in which plants can be stored over the winter. If it gets particularly cold, additional heat can be introduced into the tent. Plant heating, a frost guard or candles are suitable for this. A good place to use winter shelter tents are conditionally hardy potted plants outdoors. However, they can also be used in spring to preculture young plants. The tents are available in different sizes, they are translucent and can be reused. The disadvantage is the comparatively high price.

Antifreeze fleece

Frost protection fleece for the garden consists of a very light plastic material that is permeable to water and air. A thin layer of ice forms under the fleece due to evaporation of the soil moisture, which prevents the heat from being radiated from the soil. To avoid plastic, you can also use fleece made from 100 percent sheep's wool. Unfortunately, these have a disadvantage: they biodegrade and cannot be used again.
There is also thick construction fleece, which insulates better and does not tear as quickly as fleece for the garden. However, building fleece is not translucent and must be uncovered during the day for plants that need light in winter. Fleece can be used in many ways, for example it can be used to protect vegetable crops and young plants. You can also use the fleece to isolate trees that are more sensitive to frost. Simply wrap the fleece around the trees and tie it tight.

Coconut mats as winter protection

Coconut mats are made of a very hard-wearing material that is obtained from the outer shell of the coconut. Like frost protection fleece, they can be wrapped around plants or pots. As a regional alternative, it is recommended to use mats made from hemp. These are more durable than the fleece for the garden, but they are not translucent and usually have a higher price than frost protection fleece.

Fir twigs as winter protection

Twigs of fir or spruce can also be used as winter protection. It is draped around the grafting points of roses by bending it into a spherical shape and plugging it into one another. This isolates the soil and swirls the wind, making it less cutting and damaging to the delicate parts of the plant. You can also use fir twigs to cover up perennials or tubs. Placed flat on flower beds, it is primarily of decorative value.

Mulch as winter protection

Mulching is recommended to protect the soil and the roots and perennial organs of plants that are in it. Materials like leaves, straw, and bark mulch help retain heat and moisture in the soil. In addition, bark mulch protects like ours Plantura organic pine bark against erosion and silting up of the garden soil. In addition, the soil is sustainably supplied with carbon for building humus. The bark of pine trees impresses with its high durability, low heavy metal load and low acid content. For the sake of the environment, our organic pine bark is sustainably produced in the EU.

Jute as winter protection for plants

Jute is a long-lasting natural fiber from which bags or towels are made. It can be used in a similar way to the winter protection fleece. Jute sacks can simply be put over the crowns of plants or planters can be packed in them. However, evergreen plants should not be packed all through the winter, because jute is only weakly translucent. Jute sacks have long been used as winter protection for roses - in earlier times old potato sacks were simply put over them. Nowadays, jute is available in a wide variety of colors and this can make your garden an attractive eye-catcher in winter.

Frost protection film for plants

Frost protection film is a bubble wrap made of clear plastic. The air chambers create an insulating effect. Unfortunately, the plastic does not allow water and air to be exchanged, which means that the plants sprout too early and are more susceptible to frost and diseases. It is therefore better not to drape the film around the plant, but around the planter. Because even this must be protected from freezing through in winter. If you want to protect plants directly with the film, you should only use it for a short time, for example during night frosts in spring, and ventilate them regularly.

Frost protection candles

Frost protection candles are placed in fruit growing in spring when there is a risk of late frost, when flowers are already forming. The time in April is a very critical phase. Put the candles up late at night on nights when the temperature drops below 0 ° C. Around 8 o'clock in the morning, the worst of the cold is usually over. The candles can increase the temperature by up to 3 ° C if one or two frost protection candles are placed per 20 square meters.

Correct fertilization for frost-hardy plants

In summer, plants should no longer be fertilized with nitrogen, but with potassium - this makes the plants more resilient and better able to survive the winter. Potassium is stored in the cell sap of the plant and increases the salt content, which lowers the freezing point and increases the hardiness of frost. Avoid high nitrogen doses in autumn. These have a growth-promoting effect, the plant sprouts too early and is more sensitive to frost again. In addition, ammonium in nitrogenous fertilizers has an uptake-inhibiting effect on potassium. However, many potash fertilizers contain chloride, to which many garden plants are sensitive.

Pile up

In winter, protect perennials and the sensitive grafting areas of woody plants by piling up a thick layer of earth or mulch. This is an important frost protection measure, especially at the processing points for roses.

Not all plants should be protected from frost outside. For some, it is worthwhile to move them directly to a warmer winter quarter. You can find out what to look out for in our special article on Hibernate from planting.