Thanks to special breeding, the juniper is very robust and less susceptible to diseases. Some fungi and various pests can still cause problems for the coniferous plant.
The juniper (Juniperus) is probably one of the most popular coniferous plants in many hobby gardens in this country. The plant is generally considered to be quite robust and not particularly susceptible to disease, since there are now special breeds. Many pests and diseases do not affect them at all or hardly at all. Nevertheless, a fungal infestation, for example, can become a problem.
In the following, we will tell you in detail which pests and diseases can be expected in juniper and what you can do about them.
Brown shoot tips of juniper
Even if some hobby gardeners might think that their own juniper is sick because the tips of the shoots are turning brown, this is usually not the case. Rather, it is often not a sign of illness, but an indication of a lack of light. This problem is therefore relatively easy to solve by simply moving the juniper to another location where it gets enough light.
Only if it is an older juniper would this move become a problem. Unfortunately, an older plant often dies after transplanting. Then you have to eliminate the lack of light in other ways, which can mean, for example, cutting back a tree or other plants near the juniper.
Juniper Diseases
A fungal attack can also be a problem with juniper, since, as already mentioned, it is a coniferous plant. However, if you want to stop the fungus, you should not only remove the affected parts of the plant. Rather, it is also advisable to use a suitable pesticide from a specialist dealer. The choice of an agent on a purely biological basis is to be preferred. Other diseases that can affect juniper include these clinical pictures:
- Dying instincts
- Juniper Blister Rust
The dieback is also due to harmful fungiattributed and therefore to be treated in the manner already mentioned. In the case of juniper blister rust, on the other hand, shoots that are already lignified and very dry thicken. These blisters are gelatinous in texture and rust-red in color. They form mainly in the spring. Juniper blister rust is also known as pear rust.
Tackling Juniper Blister Rust
This disease can cause quite a lot of damage because the juniper then loses its leaves early. If the plant is affected several times by juniper blister rust, it is noticeably weakened. To prevent things from getting that far in the first place, prophylactic measures make sense. From the time when the leaves begin to sprout, spraying with horsetail extract is recommended. Potassium-rich foliar fertilizers can also be used as a preventative.
If the juniper is already infected with pear rust, control should be carried out immediately during the infestation, i.e. at the time when the very distinctive spore sacs are developing. If only a few branches are affected, these are simply cut back until only he althy wood remains. Pesticides can also be used.
If the leaves are already discolored with conspicuous dots as a result of the pear rust, this measure is no longer of any use either. However, if you prefer not to bother with the problem of pear rust, you can also choose varieties that are not or only very rarely likely to be affected.
Infestation of juniper trees
Not only diseases, but also pests pose a threat to juniper. In this context, the following pests should be mentioned in particular:
- Tree or bark aphid
- Juniper leaf miner
- Juniper Lid Scale
In the event of a lice infestation, the pests suck the juniper. In the worst case, this can lead to the needles and shoots of the plant dying off completely. If it is an infestation with the juniper cover scale, this can also lead to a discoloration of the needles. The more the lice suck on the juniper, the more the plant's growth is inhibited.
However, the so-called juniper leaf miner is the pest that most often becomes a problem. This is a small butterfly that is only about five millimeters long and is indeed reminiscent of a moth. For the caterpillars ofIn terms of pests, the juniper is a feast for the eyes. The main reason why the damage is so great is that the larvae of the juniper leaf miner work their way from one shoot to the other, causing the tips of the shoots to die off.
» Control measures:
To prevent moth infestation, all hobby gardeners should use special insecticides that are approved for this purpose. It is particularly important to spray these when the moths are about to fly. In autumn and summer, however, it can also be very useful if the shoot tips that are already affected are simply cut off. To do this, however, you should make sure that you monitor the he alth of the juniper as closely as possible so that you can intervene in good time.
Even with a lice infestation, pesticides are only helpful if they are used as early as possible. You should therefore intervene as soon as an infestation begins. If the needles of the juniper have already noticeably discolored, it is already too late. Injections can then safely be omitted, as they can no longer have any effect too late.