Nowadays, organic methods of plant protection are becoming more and more popular. This is also true for hostas, many gardeners tend to use organic pesticides instead of chemicals.
You can definitely use neem oil on your hostas. Dilute the neem oil in water and spray the leaves and stems. You can easily control pests on your hostas this way.
Next, we will discuss all the details of using neem oil. I will also tell you what to avoid when working with this product and a lot of other useful information.
What is neem oil?
Neem oil is a product that is extracted from the seeds of the neem tree, the scientific name of which is Azadirachta indica. People have been using this oil for centuries for various purposes, but nowadays it is very often used as an organic pesticide.
There are many varieties of neem oil depending on the method of extraction and how many times the raw material has been pressed. Cold-extracted neem oil from fresh raw materials is best for treating plants. Therefore, look for just such a product.
Neem oil is toxic if ingested. Therefore, coated hosta leaves become poisonous to insects. It also works as a repellent because it has an unpleasant odor. Even pest eggs being coated with neem oil will die.
Neem oil can control most hosta pests:
- Wooly Aphids;
- Pill bugs;
- Leaf beetles.
However, ineffective against grasshoppers and weevils. Chemical insecticides should be used against these pests.
How do you use neem oil on hostas?
To use neem oil on your hostas, you need to prepare it first. You can use a ready-to-use mixture that is available for purchase online or at garden centers.
To be sure of the effectiveness of the mixture you can make it yourself. To do this, buy cold-pressed neem oil concentrate. Give preference to a quality and reputable supplier.
The second ingredient you will need is organic liquid soap. Soap is needed to dissolve the oil in water. Without soap, the oil will collect on the surface of the water and the mix will not be effective.
Mix one tablespoon of soap in one gallon of warm water. Then add two tablespoons of neem oil to it. Then mix everything thoroughly and fill the sprayer with this mixture. Shake the mixture one more time before use.
Treat in the morning or evening when the sun is mild. Spray both sides of the hosta leaves. Also treat the leaf petioles.
That’s all, usually, one treatment is enough, but repeat if necessary.
Is neem oil safe for hostas?
Neem oil is safe for the hosta if used properly. But sometimes you can make a mistake and cause problems as a result, so let’s discuss this.
The first time neem oil can damage a hosta is when you apply it in sunny weather. Drops of the solution will increase exposure to the sun’s rays and the leaves will get burned.
To avoid this, apply the neem oil in cloudy but not rainy weather. You can also solve this problem by spraying the hosta early in the morning or late in the evening.
The second problem is applying too often. As a result, the leaves lose their ability to release oxygen and moisture and die. To prevent this from happening, apply neem oil no more than once every two weeks.
A final problem is a too much oil in the solution. This can burn the leaves as the neem oil concentrate is quite aggressive. To avoid this, do not use more than 2 tablespoons of neem oil per gallon of water.
If you violate the above recommendations for any reason, wash the neem oil off the hosta leaves immediately. Simply hose the hosta over the leaves for a few minutes. Repeat this after 1 to 2 hours.
How long does neem oil last on hostas?
Neem oil is most effective a few days after application. Then the effect will last in one way or another for about a week. Much depends on whether it has rained or not.
This is quite enough time to kill most of the pests that have settled on the hostas. But if necessary, repeat the spraying.
Repeated spraying should not be done earlier than 2-3 weeks after the previous one. I warned about too frequent applications in the previous chapter.
If the pests are not gone after the second use of neem oil, then you need to use a stronger product. The best pest control agents are systemic pesticides.
Avoid using neem oil as a preventative. It won’t get you the results you want. It is best to keep an eye on your hostas and spray as soon as you see pests on them.
What else can neem oil do for the hostas?
In addition to pest control, neem oil is able to rid the hosta of powdery mildew. This is actually very handy because you actually have a pesticide and a fungicide in one bottle. Neem oil has proven to be very effective in fighting this disease.
Although powdery mildew is not a very common hosta disease, it can still happen. This disease affects leaves that become covered with white powder (hence the name).
Over time, the leaf darkens and dies off. If severe, the plant can lose all of its leaves.
You can cure a hosta of powdery mildew with neem oil just as you can get rid of its pests. Simply spray the leaves as I described above and repeat the spraying after a few weeks.
Alternatives to neem oil for hostas
The good news is that there are alternatives to neem oil. If for some reason you do not want to use this product, there is a wide range of other products.
The first thing to mention here is the insecticidal soap. This is a very effective product that works with most insects. It is less toxic than other chemicals and is safer for hosta leaves. It usually comes in a ready-to-use form.
The second substitute is horticultural oil. There are a number of brands that offer oil that can also control pests. Unlike neem oil, garden oil is of mineral origin and is a fairly effective organic pesticide.
The third option is systemic or contact insecticides. This is a very powerful argument for insect control. A systemic insecticide can protect the hosta for quite a long period of time. The disadvantage of these products is that they are toxic.