RM43 weed killer is rainproof 2 hours after application. So, you can spray RM43 onto dry weeds 2 hours before rainfall or watering. Avoid spraying RM43 onto wet weeds and brush. Water can cause the RM43 to run off instead of being absorbed by the weeds. Always be careful to contain your RM43 spray to unwanted plants only. Because it contains both glyphosate and imazapyr, RM43 kills all types of plants. Plus, it prevents new plant growth for 12 months wherever it is sprayed.
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Can You Apply RM43 Before it Rains?
You can spray RM43 before rain as long as the following two conditions are met. First, the vegetation you are spraying must be dry. Second, there must be no chance of rain for the next 2 hours, at minimum. When sprayed onto dry weeds and brush, RM43 is rainfast in 2 hours. This is a quick drying time, so you can spray RM43 even if rain is in the forecast for the same day.
- The weeds you are spraying with RM43 must be dry at the time of application.
- Only apply RM43 if there is no rain in the forecast for at least 2 hours.
- Never spray RM43 on wet plants—the weed killer may not work.
- Do not spray RM43 if rain is forecast to arrive in less than 2 hours.
It is best to avoid spraying RM43 on plants that are already wet from rain, watering, or dew. Moisture on the leaves can prevent the RM43 from drying properly. The herbicide may run off the leaves and be ineffective. Wait for a dry spell and spray once the morning dew has dried off the vegetation.
What Happens if it Rains After You Spray RM43?
Rainfall less than 2 hours after applying RM43 will cause the herbicide to run off the plants before it can be absorbed through the leaves. This means the plants you intended to kill will not be harmed. Usually, the RM43 will be completely diluted and washed away, wasting your efforts. In a worst-case scenario, the RM43 runoff may travel to other nearby plants and damage them.
- Precipitation or watering less than 2 hours after spraying RM43 can dilute the herbicide and render it useless.
- In some cases, rainfall occurring too soon after application can cause RM43 to spread to desirable plants.
- RM43 can be carried through soil by rainfall months after application.
- Take care when spraying RM43 on slopes or near desirable plants, since rain can spread it through the soil.
One drawback of RM43 is that rainfall can cause it to travel through the soil, even after it has been absorbed by the weeds you intend to kill. This is one factor to consider if you are trying to decide between RM43 or Roundup. RM43 can run downhill when it is carried by water runoff or snowmelt. This can spread the RM43 and kill desirable plants.
Is it Better to Spray RM43 Before or After Rain?
It is better to spray RM43 on poison ivy and other unwanted plants before rain, when the plants are dry. This is because the active ingredients in RM43 are absorbed through the leaves of plants. If the leaves are wet, the RM43 will be diluted and is less likely to be absorbed. Just make sure your RM43 spray has at least 2 hours to dry before rain arrives.
- Whenever possible, spray RM43 before rain arrives.
- Spraying dry plants prevents RM43 dilution and runoff.
- As long as you allow the plants and ground to dry beforehand, you can spray RM43 after rain.
If you must spray RM43 after rainfall, wait until the rain has dried from the leaves, stems, and branches of the plants. It is also a good idea to wait until the ground is dry, so RM43 is not carried to nearby plants by water runoff. Remember, RM43 is a powerful non-selective weed killer that kills every plant it is sprayed on. Plus, RM43 remains active in the soil for up to 12 months, preventing any new growth in the area.
Does RM43 Need to be Watered In?
Never “water-in” RM43. Although RM43 works as a pre-emergent herbicide or “weed preventer,” it does not require the same “watering in” step that some pre-emergent herbicides need. Instead, RM43 needs 2 hours of dry conditions in order to start working.
- RM43 does not need to be watered in.
- Watering RM43 after application can stop it from working or cause it to run to other areas.
- There is no case where watering improves the effectiveness of RM43.
Rainfall and watering do not improve the performance of RM43 under any circumstances. This systemic herbicide works when it is absorbed by the leaves of plants and grasses in dry conditions. Once it is absorbed, RM43 travels throughout the plant’s system, killing the plant and its roots. Then, RM43 remains in the soil for 12 months to stop any new plants from sprouting in the area.
Can You Spray RM43 Around Trees?
Do not spray RM43 within 6 feet (2 meters) of trees that you do not wish to kill. Airborne spray can drift onto tree leaves during application. This will cause the RM43 to begin attacking the tree, which may weaken or kill it.
- Avoid spraying RM43 on unwanted weeds within 6 feet of trees.
- RM43 is deadly to trees.
- RM43 spray that lands on tree leaves will begin to systemically kill the tree.
- Because RM43 can travel through soil to attack tree roots, do not spray it on weeds near the base of trees.
Another reason to avoid spraying RM43 near trees is to prevent it from attacking tree roots. Once it is sprayed on a plant, RM43 travels to the roots and remains in the soil for up to 1 year. Watering and precipitation can spread the RM43 through the soil, which can cause it to attack trees from the roots up.
How Long Does it Take RM43 to Dry?
Effectively using RM43 requires the right weather conditions. When using RM43, keep these facts in mind:
- RM43 dries rainfast 2 hours after application.
- You can expose RM43 to watering or rainfall 2 hours after you spray it.
- RM43 must be sprayed on dry plants for it to be effective.
- There is no need to “water in” RM43 after you spray.
- RM43 kills all types of plants and prevents plant growth in soil for up to 12 months.
- It is possible for precipitation to carry RM43 through the soil to nearby plants for months after application.
- Do not spray RM43 within 6 feet (2 meters) of trees and desired plants.
RM43 is an extremely powerful weed and brush killer that destroys broadleaf weeds, grasses, and woody plants. As long as it is sprayed a safe distance from desirable plants and given time to dry, it is very useful for stopping unwanted weeds.