If you are a regular weed user and live in a US state where it is legal, chances are you have already tried your hand at growing your weed. If you haven’t tried it yet, well, there is a lot to learn. Growing cannabis is tricky even for experienced growers. It all starts with the cannabis seed. If the seed you plant is Composting occurs when organic materials—such as yard trimmings, food wastes, and animal manure— decay to form compost, that can be used to improve soil.
How Long Do Cannabis Seeds Last In Storage?
If you are a regular weed user and live in a US state where it is legal, chances are you have already tried your hand at growing your weed. If you haven’t tried it yet, well, there is a lot to learn.
Growing cannabis is tricky even for experienced growers. It all starts with the cannabis seed. If the seed you plant is no good, then you won’t get a plant at all. If you plant a seed of poor quality, then your plant will likely be of poor quality too.
If you want your cannabis plants to be healthy and potent, then the seeds your start with need to be healthy and from a good strain of cannabis.
Some people that grow their cannabis prefer to purchase their seed online, while other growers prefer to save and store seeds from their plants. How cannabis seeds are stored for later use is of the utmost importance.
How Can I Tell If Cannabis Seeds Are Good?
If you are going to go to the trouble of storing cannabis seed long-term, then you want to make sure you are storing only good seeds. After all, what would be the point in storing bad seeds? Most of the time you can tell a good quality of a cannabis seed by the way it looks.
Healthy cannabis seeds will have darker shades of gray and black on the outer shell. These darker colors can also signify genetically superior seeds.
Healthy seeds should also be firm to the touch and have a glossy and wax-like look to the shell. If you roll the seed between your thumb and index finger and it feels firm, then it should be a good seed to plant and should store well in the right conditions.
Effects Of Humidity On Cannabis Seeds
How you store your cannabis seeds works in much the same way as when you store your cannabis. Humidity can play a huge factor in how well your seeds stay preserved and for how long. In fact, humidity plays a major role in the entire lifecycle of the cannabis plant, from seed to storage of the finished flower, and ending in consumption. We even have a guide to rehydrate your cannabis if you fail to keep it moist enough and even have information on freezing your cannabis, which can cause mold issues quickly. But I digress.
Too much humidity can cause seeds to become soft and mushy or germinate. If there is no humidity at all, they can become dry and brittle and crack open.
Cannabis seeds store ideally at 20% to 30% humidity. If the humidity level is higher at 40% to 60% humidity, they will likely germinate. At 80% to 100% humidity, they will drown and wilt in as little as 12 hours.
If the humidity level falls below 20%, the seed may heat up and sweat, develop fungi on the outside as well as the inside. At the lowest humidity level of 10% or less, the seeds can attract insects or pests.
Best Storage Methods For Cannabis Seeds
Keeping your cannabis seeds cool and dry at a consistent temperature and humidity level is essential. First, you need to pick your storage container. It should be air-tight and keep out UV light if possible.
It can be a glass container with a sealing lid. Ziplock baggies are alright to store seeds in if you do your best to remove as much air as possible.
Storing your seeds in a cupboard or closet shelf is fine for short-term storage. Never store your seeds outside in a garage or shed because the constant temperature changes of day temps and cooler night temps will not be good for them.
For more long-term storage, you can always refrigerate your seeds. The refrigerator will keep the seeds at a cool, constant temperature.
Refrigeration can preserve your seeds for several years or more, but it is probably best to use them before this amount of time goes by. Freezing your seeds is possible, but necessary.
Composting to Kill Weed Seeds
Composting occurs when organic materials—such as yard trimmings, food wastes, and animal manures— decay to form compost, an earthy material that can be used to improve garden soil. Compost benefits gardens by:
- Supplying many nutrients that plants need
- Improving the soil’s physical characteristics, such as texture
- Enabling the soil to better hold water and nutrients
- Helping aerate the soil
The composting process also naturally kills weed seeds. Properly managed, a compost pile should easily reach 140°F, which breaks down all organic matter, including weed seeds.
The key word is properly . Organic matter that is improperly composted can introduce problems into a garden. Raw animal manure often contains disease-causing organisms such as E. coli and Salmonella, which can make people sick if they eat vegetables contaminated with them.
Manure can also contain live weed seeds. These seeds can spread easily from one farm, field, or garden to another, multiplying the problem from one weed to thousands of new weeds.
Figure 1. Build your compost pile with alternating layers of green matter (grass clippings), and brown matter (dead leaves), to maintain a proper carbon-to-nitrogen ratio.
How does composting reduce weed seeds?
Proper composting occurs under the following conditions:
- The ratio of carbon to nitrogen (C:N) ranges from 25:1 and 40:1. This ratio balances both energy (carbon) and nutrients (nitrogen).
- The compost is about 40 to 60 percent moisture by weight.
- The oxygen content is 5 percent or more.
- The pH level ranges from 6 to 8.
In these conditions, microorganisms begin breaking down the organic residues and releasing heat. A clear sign that the compost is decaying properly pile is the release of steam when the surface of the pile is disturbed (Fig. 2). As the temperature rises above 113°F, heat-loving microorganisms replace the earlier microorganisms. At that stage, the pile will enter the active phase, with temperatures reaching 131 to 170°F in 1 to 3 days.
Figure 2. The release of steam from a compost pile when its surface is disturbed indicates that the compost is decaying properly.
These high temperatures are the key to killing weed seeds in a compost pile. In general, more seeds will die the longer that the temperature in the pile remains within this range (Table 1).
How to compost properly
Most gardeners have a static compost pile. They believe that composting consists of filling the pile, waiting a few weeks, and then magic happens—the compost is ready. In reality, most compost piles are merely trash heaps of garden and kitchen waste.
To compost properly, keep the C:N ratio at 25:1 to 40:1 and the moisture, oxygen, and pH in the pile at optimum levels.
C:N ratio: To maintain the correct C:N ratio, build the pile with alternating layers of brown matter such as dead tree leaves, and green matter such as grass clippings. Adding equal amounts of green matter (grass clippings, kitchen waste) and dry matter (dry leaves) will often achieve this desired ratio.
Moisture: Water the compost pile regularly to keep the microorganisms alive and to soak the weed seeds fully. Don’t add so much water that it flows out from the bottom of the pile.
pH: pH meters are available in garden centers and can be used to estimate the pH level of the compost pile. However, an easy and more practical way to tell whether the compost pile is “cooking” properly is by its smell. If the compost pile smells sour or like a rotten egg, the pH is not correct. A compost pile at the proper pH should smell earthy, like freshly dug garden soil.
If the pile smells bad, check to see if it is too wet. You may be adding too much water or wetting too often. Let the pile dry for a while, and wet it less often. Another option is to turn the pile and mix it thoroughly.
If the first two measures do not help, mix lime into the pile to correct the low pH level and reduce the rotten egg smell.
Turning: Periodically mix the materials within the pile to introduce more oxygen and distribute the moisture evenly (Fig. 3). To add as much air into the pile as possible, break up any clumps, and move the drier material from the outer edges into the center.
Figure 3. Watering and turning the compost ingredients regularly will help keep microorganisms alive, aerate the pile, and distribute the moisture evenly.
Turning the compost will also enable the temperatures at the edges and surface of the pile to rise high enough to kill weed seeds. The pile must be mixed thoroughly during the active phase to ensure that all the material is heated for a long enough period to kill the seeds.
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