Our website is intended for adults only (18+)

By using this website, you confirm that you are 18 years or older and agree with our Privacy and Cookie Policy

EUR English

Stretching In Cannabis Seedlings: Why It’s A Problem And How To Solve It

Last updated: 22 September 2023

stretching in cannabis seedlings

It’s no secret that rapid growth and plant mass gaining is something every grower works toward achieving with their cannabis. However, if you notice your young weed plant quickly stretching upward while still looking thin and weak, this type of growth is indicative of a problem. In this article, we’re going to look into the phenomenon of abnormal stretching in marijuana seedlings, learn why it’s a problem, and work out how to fix it or prevent it from ever occurring again.

Why Is Stretching A Problem?

If you’re a novice grower, you might be happy seeing your weed seedlings stretch toward the sun (or its artificial replacement). However, that’s when you need to start judging the nature of growth with a grain of salt. Do the seedlings look leggy? If so, what you see is abnormal stretching. Seedlings are extremely gentle, and their root system hasn’t developed well enough yet to support a tall plant. In addition, the main stem in the seedling stage remains thin and weak. Considering stretching, all of these factors may contribute to the baby pot plants falling and even breaking. That is something the young plant very likely won’t be able to recover from.

Choose the most potent strain

Optimal Environment For Cannabis Seedlings

weed seedlings stretching

If your seedlings stretch, it basically means one thing: the young cannabis is trying to survive. Therefore, you should understand that the conditions in which you’ve placed your marijuana sprouts aren’t ideal as a stable development. So, what are the optimal conditions for cannabis seedlings? In most cases, the best thing you can do for your baby pot plant is to provide them with plenty of light and water. Soon we’ll explain the details, but for starters, make sure you keep the soil moist around the clock and don’t let anything cast a shadow on the growing plants.

What Causes Stretching In Weed Seedlings?

As we’ve already said, if your seedling is stretching, it’s trying to survive. Those tiny leaves on the top of your cannabis seedling are its solar panels that generate energy for the plant’s growth. Hence, the main reason behind abnormal stretching is that the baby weed is trying to catch more light on its solar panels by raising them up and turning them around. High temperatures and insufficient nutrients might also cause stretching. Very often, this abnormality is caused by a combination of harmful factors, so be sure to check and fix everything!

easy-to-grow weedVIEW ALL

How To Prevent Or Stop Stretching

Have you just noticed that your baby cannabis plants are taller than they should be? Or are you just checking in to avoid this problem in the future? Either way, you’re in the right place – now that we’ve covered why stretching is a problem and what causes it, it’s time to learn what can be done about it.

Fix The Main Reason – Insufficient Light

how to stop stretching

You might think that if you keep your marijuana seedling under a powerful light source such as an LED or even an HID, you’re providing the new growth with enough light. Well, that’s not exactly correct. Another crucial aspect when setting the light for weed seedlings is the distance between the young plant and the light source. Because its leaves are so small, there’s only a tiny surface available for the absorption of light, meaning the closer the source is, the more light will actually become available for the seedling. It might be easier to understand with an example, so think about this: a 200W lamp placed right under the ceiling far from the seedling will be ineffective and cause stretching, while a 20W lamp placed 10cm (4 inches) above the young plant will provide it with enough light for healthy growth.

Take Care Of The Heat

stretching in marijuana seedlings

When trying to give your seedling as much direct light as possible, make sure the light source isn’t emitting too much heat. There’s a direct correlation between the air temperature and stretching of cannabis seedlings. If you manage to keep the temperature between 60F and 80F (15-26 C), the seedlings’ stems will thicken. In contrast, when it gets hotter, the seedlings will stretch. To keep the situation under control, measure the temperature regularly and use fans to ensure proper air circulation.

Provide Air Circulation

The best part is that, by ensuring there’s no stale air in the grow room, you not only avoid the overheating problem but also directly train your seedlings’ stems. Think of it as a workout for your baby plants – the circulating air makes them swing gently, and this daily exercise on its own is extremely helpful in strengthening the stem and making it thicker.

Give Seedlings Enough Space

buy marijuana seeds for sale

You know how kids always need a lot of space to run around, play and grow? It’s the same with cannabis seedlings! You need to make sure there’s at least 10cm (4 inches) of space between the baby pot plants. That will be just enough to know that there’s far less reason for them to stretch! Otherwise, if seedlings are cramped together, they won’t get enough nutrients from the soil and will hinder even light distribution by covering each other. Needless to say, the quality of air circulation will suffer as well. Therefore, by spacing seedlings properly, you eliminate three problems responsible for stretching all at once.

Treating Leggy Cannabis Seedlings Right

Is it all lost if your seedlings have already stretched? Of course not! Brainy growers have come up with a couple of tricks to help your leggy seedlings out.

Method One: Staking

abnormally stretched seedlings

One of the ways of treating abnormally stretched seedlings is by providing them with additional means of support. This could be any type of stick – a bamboo stick, a plastic straw (a great way to reuse!), or even a pencil. Having some kind of vertical support will help the seedling to not fall over. If your baby weed plant is extra thin and shaky, you can also gently tie it down to the pole. Just make sure not to cause any additional stress by doing so, as that would provoke even more stretching!

Method Two: Burying The Seedling

what causes stretching

The most proven way of fixing a leggy seedling is burying it deeper. Just think of it as a regular replanting with one significant difference – you should always remember how gentle the seedlings are. To bury the green youngling deeper, make sure the soil has dried up completely and then dig the cannabis seedling out. Prepare a new, deeper hole, and place the cannabis sprout in it. Loosely cover this hole with soil and voila! Now the ground itself will help the seedling strengthen and gain thickness.

Stretch No More!

We all want to see marijuana plants we’re so excited about strong and healthy from day one. Sometimes, however, we get off to a rough start like with a weak, leggy seedling. Hopefully, you now know that it’s not something to worry about. When taken care of early enough, this problem won’t affect the rest of the grow. Remember, at the end of the day, a weak seedling never means a weak tree!

Herbies Head Shop expressly refuses to support the use, production, or supply of illegal substances. For more details read our Legal Disclaimer.

Hi, thanks for this article.My first two seedlings were quite stretched due to my impatience, I germinated them without adequate lighting - my tent wasn't ready yet.Turning on the light and propping them up with a dowel stick fixed that and they are now able to stand on their own....My grow tent is a very budget one.It is 2/3 sq. M. and I have used LED floodlamps (6500K) as the primary light source, I have 400W in all and the plants seem to be OK so far.I am about 3 weeks into my first grow.
Tommy Pinkcloud
Dude same! Sanaa me I’ve literally am at your step and progress. Snapchat is Tommypinkcloud
Hello Zimbo,Thank you for sharing your experience. Indeed, the lighting is a very important part of the process, never a bad idea to calculate how much light you would require for the pot installation
Add a comment

How to post a comment

Thank you for leaving a comment for us!

Your feedback will be posted shortly after our moderator checks it.

Please note that we don’t publish reviews that:

  • Are written in ALL CAPS
  • Use aggressive or offensive language
  • Promote other websites (include contact details or links)