Many people say that peppermint is a particularly easy plant to keep, and it can spread when planted in a pot or in a yard. But if you plant some potted mint yourself, you will find that it is particularly prone to various diseases and insect pests, the branches and leaves are inexplicably withered, black rot, and the leaves continue to fall.
Symptoms and treatment of peppermint pests and diseases:
In the process of conserving peppermint, it will be infected with various diseases and insect pests, the most common diseases are rust, spot blight (white star disease), and white silk disease. Conserving occasional (relatively few insect pests) of potted mint includes the twill moth, the silver moth and the small ground tiger.
First, common diseases:
1. Rust
Potted mint, during the maintenance, there will be some yellow or brownish yellow spots on the stems and leaves, these spots have some rust-like powder, in the later stages of the disease, brown spots will become black spots, gradually become black patches, this is rust.
When a peppermint potted plant is infected with rust, it will cause the leaves to continue to dry out and lose, and finally the stem and leaf parts on the ground will directly wither.
Once potted mint is found to be infected with rust, be sure to support spraying germicides to remove diseased leaves. It can be sprayed with common triazolone, powder rust and zinc solutions, generally sprayed every 7 to 10 days, and sprayed 2 to 3 times continuously to play a better effect.
2. Spot blight
Spot blight is also a more common disease when maintaining potted mint, its leaves will appear some irregular markings, or circular markings, markings are dark green at the beginning, the leaves will become dirty, slowly there will be some brown or gray-brown markings, the edges of the leaves will also become gray, and then the leaves as a whole will appear wilt and yellow.
Once the potted mint is found to have spot blight, it is necessary to remove all the diseased leaves in time, and all the fallen leaves on the soil surface should be removed cleanly, and the fungicide can be sprayed in time, which can be used to the common daisen manganese zinc, Bordeaux liquid or methylthiocycline.
3. White silk disease
After the peppermint potted plant is infected with white silk disease, the bottom of the entire branch will directly decay, its leaves are obviously still emerald green, but the bottom of the branch becomes black and rotten, and it is particularly easy to breed white silk disease in wet conditions. There is a difference with powdery mildew, which is the appearance of white powder on the leaves.
After peppermint breeds white silk disease, it will cause the whole plant to grow weaker, and eventually the whole plant will wither.
Once peppermint is found to be infected with white silk disease, be sure to remove the entire plant and remove the surrounding soil. Spraying germicidal drugs in time can be used to the common dixone.
Second, common pests and treatment methods:
The chance of peppermint infection is still relatively small, but it is also necessary to pay attention to prevention.
Above is the infection of whitefly, can be sprayed directly with imidacloprid, the leaf surface leaf back spray evenly.
If it is infected with aphids, it can be removed by spraying imidacloprid in time.
1. Silver-striped nocturnal moth and twill moth
These two kinds of nocturnal moths will lay eggs directly on the leaves of mint, their larvae will slowly hatch, and then they will nibble on the leaves of mint, if you find that the leaves of mint are constantly being eaten, and there are many holes in the leaf surface, that is, the larvae of the nocturnal moth are in trouble.
At this time, you can spray insecticides in time to remove them, such as the common anti-taibao emulsion or borer pine, but do not spray in the first 20 days of eating mint.
There is black feces on the leaves, which is basically a nocturnal moth larvae
The best way is to remove all the insects by hand, that is, to find all the eggs and leaves of the insects one by one, and to remove the larvae, which can be directly strangled by hand larvae.
2. Small land tiger
If you find that your mint itself grows better and the leaves grow healthier, but there are no new shoots.
The bottom of the mint will grow a lot of walking stems, and some new shoots will grow on the top of the stems, and if there are small ground tigers in the soil, they will eat the young shoots of the plants, which is particularly easy to occur in the spring.
If mint has not been able to germinate new shoots, it is likely to be harmed by small land tigers, and it can directly irrigate imidacloprid in the soil.
Why does the mint grow taller, the weaker the bottom?
When maintaining potted mint, we often find a phenomenon, as the branches of mint continue to grow taller, the top leaves will grow larger and grow particularly vigorously, but the leaves at the bottom of the branches will continue to become smaller, and they will dry up and fall.
In fact, the nutrients are taken away by the leaves at the top of the branches, which is the advantage of the top buds, the more leaves at the top of the branches, the more nutrients can be obtained, its growth will be better, and the leaves at the bottom of the plant will not absorb nutrients, the growth will become weaker and weaker, and eventually it will wither and fall.
If you want to make the mint plant grow more stable, you must pay attention to regular pruning, and you can be fierce (re-pruning) when pruning, but at least one or two pairs of leaves (2 to 4 pieces) should be retained at the bottom of the branch, and some leaves should be left for photosynthesis.
After pruning the potted mint, it is necessary to replenish the fertilizer in time, otherwise it will lead to a lack of fertility, and the growth will become weaker and weaker in the later stage.
The best way is to change the pot after pruning, remove the bottom topsoil, and try not to damage the white root system. After removing the topsoil, you can add some new soil, bury some slow-release fertilizer and decomposing sheep manure under the soil to ensure sufficient growth fertility in the later stage, the fertilizer should be separated by soil, and the fertilizer should not directly contact the root system.
The above is to give too much fat, resulting in fat injuries
In addition, if it is found that the surface of the potted mint grows a lot of walking stems, but also to cut off these walking stems, you can re-cut the stems to propagate, its walking stems will rob a lot of nutrients, the space is relatively limited when maintaining potted mint, and it is found that too many walking stems are found to need to be cut off.
After the peppermint potted plant is replaced by a good pot, and more bottom fertilizer is given, it can be watered, placed in a ventilated and transparent place, first do not expose to the sun, after a day or two you can slowly see the light, placed in a soft scattered light position, slowly increase the light, about 3 to 4 weeks later, the potted mint can be restored to the original state.
Peppermint still likes light, if raised in a position with more sunlight, the water must be kept up in time, it is slightly drought-tolerant, but does not like the soil long-term lack of water, especially the soil is completely dry, has not added water to it, that will only lead to its stems and leaves hanging low, and even lead to the wilting of branches and leaves.
Dead leaves and dead branches at the bottom of the mint pot must be removed in time (and check whether there are any diseases and insect pests), otherwise it will become a breeding ground for pests and diseases, especially in the rainy season, or in an environment without light, or poor ventilation, which is easy to breed pests and diseases.