Why does thuja turn yellow?
Content:
Thuja is a very beautiful evergreen plant, so any color change is a signal that something is wrong with the plant. At this moment, it is necessary to determine as quickly as possible what exactly is the cause of the plant's malaise and to eliminate all negative factors as soon as possible, then the thuja will recover and again will delight you with its fluffy green crown. There are several reasons why thuja turns yellow, knowing them you can analyze the situation, quickly navigate and start acting.
Why does thuja turn yellow: the main reasons
So, in order to determine the reason that thuja turns yellow, you need to know what factors can lead to this. It can be:
- diseases, most likely a fungal infection. - harmful insects that weaken the plant's immunity.
- insufficient nutrient soil.
- incorrect planting and lack of plant care.
- pets that “tag” the plant.
- violation of the irrigation regime, too much or too little moisture.
- due to temperature changes, the needles sometimes change color for natural reasons.
As soon as you determine the reason why the thuja turns yellow, you must immediately proceed to resuscitation measures to save the thuja.
Thuja turns yellow after transplantation. What to do?
Sometimes thuja may turn a little yellow during the first time after transplantation, and there is nothing wrong with that. The plant is under severe stress, it needs time to adapt.
But if time passes, you understand that the thuyu has taken root, but has not stopped turning yellow, then you should think about whether you made a mistake in the process of planting the plant.
And the first question to ask yourself is - did you choose the right place? Thuja is quite demanding on soil fertility. If your site has poor sandy soil, then it drains very well, which means that the thuja does not receive enough moisture. And as a result, it will turn yellow.
Heavy clay soils, on the other hand, suffer from stagnant water. This means that it can have a bad effect on the root collar. An excess of moisture will lead to an insufficient amount of oxygen in the soil. In the absence of ventilation, the roots will clog and then rot.
As a result, the plant will turn yellow and may die. If, when planting, you deepened the root collar, then yellowing will not begin immediately, but only after a few weeks. Roots in this state will not be able to resist fungal infections, and you will learn about this by changing the color of the needles.
If, after transplanting, the thuja was in shade, and then, for some reason, the source of the shade was eliminated, then it is likely that your plant received a sunburn. Bright sunlight can not only "fry" the needles, but also lead to the death of the plant.
Do not plant plants too close to each other. With a dense planting, they lack not only nutrients, but also oxygen. All this together also leads to a change in the color of the needles and, possibly, to diseases.
If you are going to plant a thuja in your summer cottage, approach this issue thoroughly. Read the landing rules, choose and prepare your seat in advance. If the planting goes well, then the plant will quickly settle down and will not turn yellow.
Why does thuja turn yellow in spring, how to identify and fix the problem
Faced with the fact that thuja needles turn yellow, one must first of all exclude natural causes. Often the lower branches of plants turn yellow. This is a natural course of events and no treatment is required. Then it should be borne in mind that some types of thuja, despite the fact that they are evergreen, turn slightly yellow with the onset of cold weather.
They will change color again in the spring, just make sure it matches the variety you are planting. But there are other reasons that we have to fight against.
- Sunburn
We have already said that direct sunlight thuye is contraindicated, ultraviolet light is especially destructive in spring. At this time, the snow has not yet melted, and the sun is already hot enough. Ultraviolet rays are reflected from the snow cover and burn the delicate needles of the thuja.
To avoid this, it is necessary to build a shelter for the plant in February. And to use for this not a spandbond, which transmits ultraviolet light, but a mosquito net or gauze. So you will definitely protect the thuja from sunburn.
- Lack or excess of moisture
Both can lead to yellowing of the plant. To avoid excess moisture, do not plant threshing water where groundwater is too close.
On the one hand, a thuja planted in such a place can hardly be watered. On the other hand, in a rainy summer or autumn, the probability of plant death from excess moisture and related diseases is high. Lack of moisture is easier to fix.
After planting, work out a watering regime by doing it every five days and using at least a bucket of water. If the plant is large, then more water will be required. Also, periodically it is necessary to arrange thuja sprinkling, but do this either in the evening hours or in the early morning.
The soil in the near-stem circle of the plant can be mulched with moss, bark or coniferous litter. This will prevent moisture evaporation.
With a lack of nutrients, chlorosis begins in many crops - their foliage turns yellow. This can happen with currants, grapes, tomatoes, why then can't this happen with thuja?
It often happens that insufficiently nutritious soil is the reason for the yellowing of plants. This is easy to fix, since thuja responds well to both organic and mineral feedings.
If you use organic matter, for example, manure, then you need to dilute it in water in a ratio of 1 to 4 and gently water the plants under the root, without falling either on the trunk or on the branches. One thuja will require three liters of solution.
If you prefer complex mineral fertilizers, then you can use "Bioud", "Epin", "Kumir-universal".
Three additional dressings can be carried out during the spring and summer. The latter should be no later than mid-August. Otherwise, new branches, which actively begin to grow after feeding, will not have time to get stronger and are guaranteed to freeze in winter. This means that by the spring they will turn yellow and dry.
Use any fertilizer very carefully, water the plant at the root. If it hits the needles, it can only increase the yellowness.
- Diseases and harmful insects
All conifers have good immunity, but this does not mean that they are completely insured against diseases, and even more so against the invasion of parasites.
So, for example, among the many species of aphids there is one called "thuya aphid". To cope with it will help drugs "Actellik" or "Porop-C".
If we talk about diseases, then most often you can encounter fungal infections - various types of rot and mold.
When "brown mold" appears, "Kartotsid" or "Bordeaux mixture" will come to your aid. It will take two treatments with an interval of 2-3 weeks.
Also, in the fight against fungal infections, the drugs Fundazol and Commander will help you. They can be used immediately after planting and then annually at the beginning and towards the end of the season.
If a pest or disease has affected a large part of the plant, for example, an entire branch, then it will be advisable to remove it and burn it to stop the problem from spreading.
- Pets
If you do not have pets, then this option can be ruled out immediately.But if there is, and at the same time the thuja turns yellow at the edges at the height of the growth, then observe, perhaps, it was the dog or cat that became the cause of the yellowing.
Thuja very negatively perceives animal feces, the yellowing of the needles will not go right away. For a while, the roots will resist and try to cope with the problem, but then they will give up.
And here it is important to know in advance that no folk remedies and special sprays will help to wean the animal from marking its territory. In this case, the only way out is to install a fence.
Yes, perhaps additional fences were not included in your plans, but in this case it is a necessary necessity. Set up a fence half a meter from the plant and the animals will have to change their habits.
Moreover, now in agricultural stores you can find a rich assortment of various plastic and other structures that will successfully fit into the landscape of the site.
Some enterprising gardeners plant thorny plants around the thuja, up to cacti. Only very stubborn and persistent animals will make their way through such obstacles.
Preventive measures
We have voiced the main problems due to which thuja turns yellow, and it is obvious that with proper care they can be prevented. For this, it is only necessary to carry out prevention.
When planting, be sure to shade the shade for the first time, until it takes root and gets stronger.
Mulch the soil around the plant. This will prevent moisture from evaporating too quickly and will protect against frost in winter. Peat, coniferous litter, compost, sawdust or dry foliage are suitable as mulch.
Remember to water the thuja regularly. Every five to seven days, a ten-liter bucket of water must be poured under it. If it is hot and there is no rain, then watering should be done more often, at least twice a week.
In addition to watering the thuja, sprinkling will be beneficial, this will also save it from yellowing. It is necessary to sprinkle either in the evening or early, around five in the morning.
Three times a season, feed with mineral fertilizers or organic matter, but be careful and observe the dosage. An oversupply of fertilizer can cause yellowing, as can a lack of fertilizer.
If the thuja regularly turns yellow every spring, then you need to take care of a good shelter for the winter. Perhaps, it is necessary not only to mulch the soil, but also to wrap the plant in burlap or geotextile.
If, on the contrary, thuja turns yellow every autumn, then it probably does not have enough time to “ripen”. Review your fertilization schedule and dosage to boost plant growth in spring and early summer.
If you have pets, you can insure yourself in advance and protect the thuja with a decorative fence. This will prevent them from ruining the plant. At the end of winter, take care to shelter the thuja from the spring sun and prevent possible burns. Use a mosquito net or cheesecloth for this.
Summarizing
So, now you know all the main reasons why your thuja turns yellow. There are not so many of them, and in most cases all these factors can be prevented if you pay enough attention to caring for the plant.
Thuja is not a capricious plant that requires daily care; any novice gardener will cope with planting and growing it. It is easier to prevent any problems than to deal with their consequences later.
Following the rules of agricultural technology and providing the plant with the most comfortable conditions, you will get a beautiful and healthy plant that will delight you for many years.