Whitewashing trees in autumn: tips from agronomists

Let’s first find out: why do you need to whitewash trees?

The answer is simple. Fruit trees have dark trunks, they attract the sun’s rays, and at the end of winter the sun begins to bake. In young trees, it can cause bark burns. The old ones have another problem: during the day, the rays heat the trunks, and the water inside them thaws. And at night it freezes and the ice breaks the bark – the so-called frost holes are obtained. The peak of temperature fluctuations falls on the end of February – the beginning of March (1). Just think about the numbers: already in February, under the influence of the sun from the south side, the temperature in the surface layers of the crust reaches 8-14 ° C, and at night from the middle lane at this time frosts of up to -35 ° C are possible (2).

And white paint reflects the sun’s rays and solves both problems at once.

When and how to whitewash trees

There are 5 postulates that are important to consider when whitewashing.

1. Trees can only be whitewashed in warm, dry weather at an air temperature above 5 °C. During the rains, whitewashing is meaningless – the paint will immediately wash off. At lower temperatures, tree trunks are often covered with a thin crust of ice, and if the whitewash lies on top of it, it will drain in the first thaw.

2. Young trees planted this year cannot be whitewashed – whitewashing will slow down their development in the future. You can paint them only from the second year of life. But even better from the third.

3. It is necessary to whitewash not only the trunks, but also the skeletal branches – they also suffer from sunburn and frostbites.

4. Before whitening, you need to remove old, exfoliating bark, mosses and lichens from the trunk and branches. All wounds must be covered with garden pitch.

5. You can bleach until mid-January – no later! Because it is in the second half of winter that burns and frost cracks appear. You may simply not have time.

How to whitewash trees

There are several options for whitewashing trees in the fall, and each has its pros and cons.

Lime. It has two advantages – it is environmentally friendly and inexpensive.

But there are many cons.

Firstly, it does not hold well – it is washed off literally in 2 – 3 rains. Therefore, it is better to whitewash with lime in winter, and not in autumn. But this is problematic, since this can only be done during a thaw and it is not a fact that they will fall on the weekend. And will they? By the way. If milk is added to the lime, it will adhere better to the trunks. But this will not help much – it will not wash off so quickly, but still ahead of time.

Secondly, lime only protects against frost and burns. From pests and diseases – no. You can add copper sulfate to it – it will protect the trees from diseases, but this is an additional waste of money, and most importantly, time and effort.

Thirdly, lime is harmful to young trees – it draws moisture from tissues and plants suffer from dehydration.

Water based paints. Just like lime, they protect only from burns and frost cracks. There are no additional components. And you can’t add copper sulfate to them – the paint darkens from it and loses its protective properties.

But they are better than lime, if only because they are not washed off – they last all winter.

Acrylic paints. They are superior to other whitewashes in many respects. They also keep well on trees, sometimes until May. But most importantly, they include additives against diseases and pests. And they do not harm young trees. Moreover, they, on the contrary, retain water in the bark, preventing it from evaporating, but at the same time they allow air to pass through and plants can breathe.

They have one drawback – they are more expensive than other whitewashes.

Clay with mullein. From an environmental point of view, this is the best option. It is this whitewash that is used in Europe on eco-farms.

It is easy to make: the clay is diluted with water to the density of sour cream, mullein is added there, you can still ash, everything is thoroughly mixed and the trunks are whitened. Clay perfectly protects trees from sunlight and winds, while allowing the bark to breathe. And the mullein reliably “glues” the clay to the trunk and prevents it from falling off ahead of time. In addition, it contains a lot of bioactive substances that benefit the tree.

By the way, iron sulfate can be added to this mixture – there will be additional protection against diseases. And it looks beautiful – this whitewash has an unusual yellowish-light green hue.

One problem is that it is difficult for a city dweller to get a mullein.

Popular questions and answers

We talked about whitewashing trees with agronomist-breeder Svetlana Mikhailova.

Sources of

1. Romanov V.V., Ganichkina O.A., Akimov A.A., Uvarov E.V. In the garden and in the garden // Yaroslavl, Upper Volga book publishing house, 1989 – 288 p.
2. Chirkov L.S. Handbook of the gardener and gardener // Samara, Publishing House of the Samara OK KP RSFSR. 1991 – 256 p.