The Content Of The Article:
- New shoots are particularly at risk of late frost
- Protect frost sensitive plants in time
- Late frost damage to fruit trees
- Remove frozen shoots promptly
The tricky thing about late frost is that even hardy plants are often defenseless. If frost-resistant trees have stopped growing in autumn and their shoots are well lignified, even severe frosts can hardly harm most species. The same applies to perennials as soon as they are "drafted", as it is called in the gardening language. They die aboveground in the autumn and survive the winter underground in the root system or in special storage organs such as tubers and rhizomes.
New shoots are particularly at risk of late frost
If, on the other hand, the plants are surprised in the spring by a cold snap with icy temperatures, they rarely get away without damage. Particularly affected are mostly plant species whose winter hardiness is borderline anyway, such as hydrangeas, lavender or evergreen woody plants such as the cherry laurel. But the native red beech are late frost sensitive and their new shoots often freeze completely back.
In the Rodgersie (left) only a few leaves are frozen. New foliage is pushing through it again. The new shoots of the Blood Beech Hedge (right) are completely dead. Here is an early hedge cut makes sense
The good news is that late frost does not seriously damage winter hardy plants. As a rule, only the new, yet unholzholz shoots freeze. Although this is not optimal, but grows in the course of the season, as the perennials and shrubs below the dead drive parts again expelled.
Protect frost sensitive plants in time
The situation is somewhat different for vegetables and balcony flowers, provided they are not frost resistant. For example, those who have already planted their tomatoes outdoors in front of the Eisheiligen must expect a total failure. In the case of potatoes, on the other hand, the damage is usually limited - they are well protected in the ground and push through again. The yield is still smaller after frost damage.
With a fleece cover you can protect young salad seedlings from frost
Effective protection for outdoor plants is a fleece cover or a foil tunnel. As a precautionary measure, lay out a large piece of garden fleece or special fleece hoods so that you can quickly cover the vegetable beds or individual plants in the evenings if night frost threatens. If you have already planted your window boxes with petunia and other summer flowers, you should simply put them in the house or in the garage overnight.
Late frost damage to fruit trees
By the way, late frosts are especially problematic for fruit growing. If the temperatures fall below the zero-degree mark during the cherry or apple blossom, this often means large crop losses, because the flowers freeze very easily. In addition, in prolonged periods of cold only a few insects on the way - so much fewer flowers are fertilized than at higher temperatures.
Sweet cherry plantation after an antifreeze irrigation
However, there is an ingenious trick, with which the fruit growers often can still save a large part of the harvest despite frosty nights: This is achieved with a so-called Frostschutzberegnung. With special nozzles that spray the water finely, the trees are moistened just before the frost. The water settles on the flowers and leaves as a thin ice sheet, protecting it from even more frost. Under the ice, the temperature is still slightly above zero degrees in light frost, so that the flowers are not damaged.
Remove frozen shoots promptly
If the frost has already struck, a timely pruning of the plants is important. The dead shoots are only unnecessary ballast for the trees and shrubs. The sooner you remove them with the pair of scissors, the sooner the plant can activate the so-called sleeping eyes beneath the frozen parts of the shoot and drive them out again. If you then help out with some quick-acting fertilizer, such as blue-grain, the frost damage will not be visible after a few weeks.