How to Fix Stunted Growth in Plants

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It’s important to remember that, at their core, cannabis plants are much more delicate than you might imagine. Even slight changes to the environments in which you grow your plants can have huge effects, some of which can be catastrophic.

Somewhat less problematic, though, are those problems that slow down your harvests and make you wonder about the health of your plants. One common issue is stunted growth, something which virtually every grower will encounter at least once.

If you can learn a bit about it, though, you can figure out how to avoid this problem.

Identifying Stunted Growth in Plants

Identifying stunted growth in cannabis plants isn’t actually all that hard, but it does take at least a little experience. Simply put, you can tell that the growth cycle is stunted because the plant is either much smaller than you might have expected or it’s taking much longer to reach its full size than normal.

Obviously, it’s much easier to tell if a plant’s growth is stunted if you already have experience growing cannabis plants, as you should have a much better idea of what a healthy plant will look like when it is done growing as well as how long it should take a plant to reach maturity.

Reasons for Slow or Stunted Cannabis Growth

There are plenty of reasons why your plants might be growing slowly or not at all. In some cases, you might just be using old seeds or seeds that are simply from slow-growing plants.

In other cases, you might have a plant that’s stressed out from being cloned or one that’s just been placed poorly. Sometimes cannabis growth can be stunted because of problems with the roots or with the humidity of the room, while other times the problems have more to do with the spectrum of light that’s being used in your grow room.

How to fix stunted growth in plants

The sheer number of reasons why your plant might not be growing correctly can make it very tough to figure out how to solve the problem.

What Can You Do About Slow or Stunted Marijuana Growth?

It’s fortunate to note that in many cases, stunted plant growth is something that can be solved or at least prevented in the future. The big problem, though, is that you have to identify exactly what’s causing the stunted growth in the first place.

If it’s an issue with the quality of the soil or the atmosphere for the growing area, for example, the problem can be solved by simply making a change. If the problem is with the quality of the seeds or the plant itself, though, you’ll want to make changes in the plants that you choose to grow going forward.

Common Cannabis Growing Problems and How They are Treated

Since the methods that you’re going to use to solve your problems rely on being able to identify them in the first place, you’re going to want to start by doing some research on the most common causes of stunted cannabis plant growth. While there are actually many different potential causes, getting familiar with the most common issues is the best way to start figuring out what’s wrong with your plants.

Below are a handful of the issues for which you should look if your plants aren’t growing as quickly as they should.

An inappropriate spectrum of light

Cannabis plants are extremely sensitive to light. As you might have learned when you first started growing marijuana, the light to which you expose your plants is going to have a huge role in how they grow.

You will actually need to keep track of the spectrum of light to which your plants are exposed in each stage of their growth, as the type of lighting needs to be changed as the plant moves from the vegetative state to the flowering state in order to encourage growth.

pH of the medium used

The acidity of the medium in which you grow your plants also matters. What many new growers may not know is that there’s actually only a very narrow pH window for growing cannabis.

Cannabis plant growing on a pot with late flowers ready to harvest

If you are growing your plants in soil, for example, your pH levels need to be between 6.5 and 7. Hydro has an even narrower range, which is between 5.6 and 5.8. If you can’t keep the pH levels of your medium within those ranges, your plants simply will not be able to grow correctly.

If the acidity of the soil doesn’t kill the plants entirely, it will certainly slow their growth.

Low nutrient strength

Finally, you’ll want to look at the nutrient strength that you’re using to feed your plants. Growing marijuana is actually fairly nutrient intensive, but the plants are more stubborn than some growers might assume.

What this means is that the plants will likely keep growing if they aren’t getting quite enough nutrition, but that the growing process will still be slower. If you want to make sure that your plants are getting all the nutrients they need to grow at the correct speed, you’ll need to take a closer look at the nutrients that you are feeding those plants.

Extra Tips for Preventing Stunted Plants

Now that you know the most common causes of stunted growth, you can start to examine the way that you are growing your plants. Since it’s hard to identify many of the other issues that can cause your plants to grow slowly, you should take some other steps that will generally help your plants to become healthier and more likely to grow at the correct rate.

Below are just a few of the steps you can take to make sure that your plants not only have to best chance to grow well, but to ensure that you have a good yield.

Check the Temperature and Humidity in Your Grow Room

Your plants are more sensitive to their environment than you might imagine. Marijuana plants need a warm and humid environment to grow, but what that means can be difficult to figure out if you’re not precise about things.

Make sure that you keep a close eye on the exact temperature and humidity of your grow room throughout the day so that you can ensure that your plants are always in the right environment. If you can keep an eye on these levels, you’ll be far more likely to have plants that grow on schedule.

Keep Pests Away

Cannabis plants are also incredibly sensitive to stress. There’s an awful lot of work that you have to do to keep them happy, but one surefire way to make them stop growing is to expose them to pests.

Hands with Scissors Trimming Marijuana Leaf from Cannabis Plant

Simply put, you need to keep all kinds of bugs and fungi away from your plants if you want them to grow. When your plants get stressed, they stop growing.

If you want your plants to grow, then, you’re going to have to ensure that they get as peaceful an environment as possible by eliminating pests.

Use Supplements to Help Your Plants Recover

While taking simple steps to keep your plants happy and healthy is a good idea, that doesn’t mean that things won’t go wrong from time to time. If your plants get sick or start growing slowly, you can make use of any number of supplements to help your plants recover.

Make sure that your use supplements that are specifically known to work with cannabis plants and only use them as necessary. If you’re able to use them correctly, though, you should be able to salvage your plants and return them to a state in which they can be harvested.

Flush Your Plants

Flushing is one of the simplest things you can do for your plants, yet it’s also one of the most effective. From time to time, you need to run clean water through your growth medium.

This will help to wash away many of the contaminants that could cause your plants’ growth to be stunted and gives you a chance to create a fresh slate. You’ll want to make sure that the water you use during this process is pure, though, as adding any other minerals to the medium could end up complicating the process of cleaning up your plants.

Bottom Line

The bottom line is that stunted growth is almost certainly something that you’re going to encounter as a grower and it’s also something that you’re going to be able to use as a kind of litmus test for the environment in which you are growing your plants. While you certainly should take steps to prevent stunted growth when possible, try to use the presence of slow-growing plants as a sign that you need to make changes in your overall growing strategy.

Once you can learn to fix what’s gone wrong with your plants, you can start to make better decisions as a grower.