Over-watered vs. under-watered marijuana: how can I tell if my cannabis plant is over or under-watered?

A common question for new cannabis growers is how to tell if your drooping cannabis is over or under-watered. It's common for new growers to over-water their weed, but that doesn't mean that under-watering doesn't happen too. Never fear, it's easy to tell how often you should be feeding your plant and what is the true cause of your drooping.

An over watered cannabis plant will have leaves that are full of water, so the leaves will be firm to the touch and generally curling down (even from the stem of the leaf) almost as if it has too much water weight to hold the leaf out straight.

Over-watered cannabis plant

leaves are firm & curled

An under watered cannabis plant will have leaves that are brittle, limp, and lifeless. The leaves will seem to be drooping but won't appear as rounded and full as an over watered cannabis plant.

Under-watered cannabis plant

leaves are limp and lifeless

Click for more pictures (and more info) for Over-Watered Cannabis and Under-Watered Cannabis

How often should I be feeding my cannabis plants?

You will want to water your marijuana whenever the top of the growing medium starts feeling dry. You should stick your finger 1-2" into the soil. If things feel damp, you should wait to water again. If it's dry then you know it's time to feed your plant.

This will start out with you watering your marijuana every couple of days when they're seedlings, and may end up with you watering them once a day towards the end of the marijuana flowering cycle. You want to ensure that you have about 20-30% extra run-off water come out the bottom of the container every time you water your plants. The reason for this is that growing mediums such as soil and coco coir tend to form natural salts and concentrated pockets of nutrients (which can burn your plant) if it the fertilizers just sit in there and never get washed out. Making sure you keep adding water until you get run-off is also a great way to make sure that your marijuana plants are draining properly. If your marijuana shows signs of drooping, chances are you are over or under-watering. In order to prevent over or under-watering, make sure you water thoroughly every time, and wait to water again until the top inch of growing medium (soil, coco coir, soilless mix, etc) feels dry.

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