Underwatered Cannabis Plant? Signs, Fixes and How to Prevent It

An underwatered cannabis plant shows droopy, lifeless fan leaves, dry and crispy foliage and a fading smell; the fix is to water slowly until runoff comes out the bottom of the container, then stick to a regular schedule so the medium never dries out completely. Preventing underwatering in your weed plant is key to healthy growth and a bigger harvest, because a bad watering routine leads to wilting, slow growth and lower-quality flowers.

That's why we've put together practical tips and techniques to make sure your plants get the right amount of water at every stage. Stay ahead of underwatering and your plants will stay vigorous and ready to pump out big harvests.

What is underwatering in cannabis plants?

Underwatering can seriously hurt the growth and health of your cannabis plants. It's not as common as overwatering, but it happens for a few reasons, like a growing medium that doesn't hold water well, high temperatures or a grower who's still learning the ropes.

Here's how to spot, prevent and fix underwatering in your cannabis plants.

What causes underwatering in weed plants?

• A medium that doesn't hold water: Some growing mediums don't retain water well, so you have to water more often.
• Grower inexperience: New growers can be too cautious with the watering can and end up leaving their plants thirsty.
• High temperatures: When it's hot, water evaporates faster and the medium dries out.
• No real watering routine: Not watering at regular intervals can let the medium dry out completely, which takes a toll on plant health.

Signs of an underwatered cannabis plant

Underwatering shows up as visible symptoms on your cannabis plants. Watch for:

• Droopy, lifeless leaves: The fan leaves hang down, a sign the plant is stressed and short on water.
• Dry, crispy foliage: Leaves dry out and lose their shine and soft texture. The foliage can look worn out.
• Damaged roots: Root tips start drying out and turn thin and brittle, which hurts the plant's ability to take up water and nutrients.
• Less aroma: That signature cannabis smell fades and gets replaced by a dry-leaf smell.

How to fix an underwatered cannabis plant

You can bring back a cannabis plant that's been underwatered if you act in time. Follow these steps to help your plants recover:

• Water gradually: Don't try to make up for underwatering by drowning the plant. Instead, water slowly until it starts to run out the bottom of the container. That should take somewhere between 30 and 60 seconds.
• Keep your nutrient mix the same: Don't change your nutrient strength (EC, or electrical conductivity) to try to make up for lost time. Stick with the same formula you were using.
• Watch the water temperature: Make sure the water is between 15 and 22 °C (59-72 °F). Avoid cold water, since it can shock the roots.

• Saturate the growing medium: Make sure the medium is fully soaked until you see proper drainage.
• Use a quality medium: Pick a growing medium with a good balance of water retention and drainage.
• Water on a schedule: Set up a consistent watering schedule so the medium never dries out completely.

Put these habits into practice and you'll keep your cannabis plants well hydrated and in top growing shape, steering clear of the problems that come with underwatering.

How to keep your watering routine from coming up short

Underwatering cannabis plants is less common than overwatering, but it can still cause serious problems and stress your plants out. The key is giving them exactly the water they need, no more and no less. Here are a few effective strategies to avoid underwatering and keep your plants healthy.

Keep the growing medium moist

One of the simplest ways to avoid underwatering is making sure the medium never dries out completely. Water your plants while the medium is still slightly damp, instead of waiting for the leaves to droop, which means the medium has been dry for too long.

Check how moist the medium is

Watering every 2 or 3 days is a good rule of thumb, but don't follow that schedule blindly. If you notice the medium drying out in a day or less, you're probably not giving your plants enough water.

To figure out when it's time to water, you can use a soil moisture meter. No meter? Just stick your index finger into the medium. If it feels dry, it's time to water; if it's still damp, wait a couple of days and check again.

Lift the container to check its weight

Another handy trick to avoid underwatering is lifting the container to feel its weight. If you don't have a moisture meter, this works great. Fill a container of the same size with the same mix you're using and keep it as a reference. When you lift your plant's container, you'll be able to feel how heavy it is and tell whether the medium is dry or still holding enough water.

Follow these tips and techniques and you'll keep underwatering in check and your cannabis plants in top growing shape.