How to protect your cannabis crop from rainTrevor HenningsSeptember 19, 2019
First things first: Don’t panic. Let’s take a look at some tips and tricks around outdoor farming and rainy weather, so you can put yourself at ease.
Before the storm
First off, be prepared. When it comes to storms and cannabis, your number one line of defense is trellising. Wet buds are a lot heavier, which means you need to provide significantly more structural support than you might have anticipated.
Trellis and stake ahead of time
To begin, make sure the primary stalks of your plants are supported. Cages can be placed around plants at a young age and will work wonders later in the season. But any point where a branch splits into two new stalks is a point of stress that can easily break. Identify these points and use bamboo stakes and garden ties to secure big branches.
After securing the inside of the plant, you need to trellis the outside and provide support to the buds. Use strong building materials like rebar, 2x4s, or T-posts, and drive them into the ground next to your plants—these will support the trellis (or scrog) material.
Attach trellising to these posts so it’s taught, and then take time to guide each bud or branch through the trellis or scrog. Spacing the buds will encourage air flow and help prevent mold.
When growing in pots, drainage shouldn’t be an issue. Just make sure water doesn’t pool and stay around the pots.
If your plants are in the ground, you want to be sure soil can properly drain after a storm. Some natural drainage barriers are invisible to the naked eye, such as bedrock under the surface, which can cause your plant roots to soak in water for days after a storm.
The best way to prevent this is to check before planting. During the season before planting, pay attention to your proposed garden site and see how it responds during and after a storm. If water doesn’t drain properly, install a perforated drainage pipe through your garden to help divert excess water, or consider a new location for your garden.
Wind is a big threat to cannabis plants so when choosing a garden space, consider which way the wind typically blows and plant accordingly. By planting near dense trees or bushes you can block the wind from wreaking havoc in your garden. But be sure not to block out sunlight. A south-facing garden plot is ideal.
Also, consider the topography: Ridges might get the best sun exposure, but they are also the most exposed to wind and other natural elements. Meadows, or garden sites just below a ridge may be your best choice.
After the storm
It’s important to check your garden after a big storm. Inspect every plant, looking for damaged branches and check the buds.
Check and shake off plants
When inspecting, take the opportunity to help your plant shed some water weight by shaking the stalks. Do so lightly to avoid damaging the plant.
Check big colas for bud rot that comes from the inside. This is especially important if hot, sunny weather occurs right after a storm, which creates a high humidity environment. Look for brown spots, slimy flowers, and dead branches. If found, cut these away and discard the material away from your garden.
If you find broken branches, the quicker you can repair them the better. Zip ties or plumber’s tape can be your best friend in mending a branch. Note that it is no longer recommended to use tree tar seal, as it prevents a plant from using its own immune system.
To apply zip ties or plumber’s tape, bring the branch back as closely to its original position as possible, and use a few ties or strips of tape to distribute pressure and seal the gap. Also, consider using bamboo stakes to support the upper portion of the branch, to help take some stress off the plant.
Wait to harvest
Don’t chop your plants directly after a storm if you don’t have to. It’s a good practice to let plants dry out a bit on their own as opposed to chopping them to help dry. Attempting to dry your buds when they start out soaking wet is a recipe for getting mold in the drying room. By leaving your plants outdoors, they will have a better chance to dry off slowly.
If you do see rampant mold growth then go ahead and chop and discard moldy buds before hanging your harvest to dry.
While a big storm can cause mold, snap branches, and stress a plant, remember that with growing anything, there is a percentage of lost crops. By following these recommendations you will surely lower your loss, but there is no way to take all the risk out of growing outdoors.