The most obvious thing a person can do to show seed quality is to germinate the seed. If the seed sprouts within 5 days, it is a viable seed. It will still take time to find out if the plant will be male or female and whether the strain is high quality.
A lot of information can be gleaned from the texture and hardness of a marijuana seed. After visually inspecting the seeds, growers can pick them up and feel their shell for the following:
Germinate the Seed
While seeing and feeling a marijuana seed can give growers a lot of information, it is not always accurate. Even the best-looking seeds can be duds, especially if they have been frozen. Below are a few things growers can do to better determine the quality of their seeds.
Quality marijuana seeds have specific characteristics that set them apart. Unfortunately, they can be difficult for consumers to find since most growers avoid seed production in their plants at all costs. Even when a rogue seed is present, it rarely grows mature enough to germinate. Though it is challenging to identify a quality seed for even the most experienced growers, it is vital to be able to do so when using seeds to grow marijuana. Below is an overview of the characteristics of a high-quality seed.
Preflowers are the earliest sign of a marijuana plant’s gender. Between four and six weeks, nodes will develop at the joint where a plant’s stem meets the stalk. Female plants develop white hairs at the internodal joints while male plants develop rounded internodal sacs that fill with pollen.
In contrast, the very early female cannabis pre-flowers are more ovate in shape: pear-like, but with a longer slender pointed tip. That is called her calyx. Extending from the tip of the calyx may be a pair of pistils, or white hair-like protrusions. However, please note that not every female cannabis plant in pre-flower produces pistils.
However, the culled males don’t need to go to waste! One option is to chop up the male plant and use it to mulch other plants – much like we do with borage, fava bean greens, yarrow, and comfrey. You could also juice the leaves, which are full of nutrients. Heck, you could even steep the plant material in water to create a natural fertilizer as we do with stinging nettle. Finally, I’m sure your compost pile will welcome the male plant with open arms. Or would that be… with open worms?
Keeping in mind that every strain and grow set-up (e.g. indoors, outdoors, daylight hours) creates varying circumstances, most cannabis plants begin to pre-flower as early as 4 weeks after germination. By week 6, the pre-flowers begin to reveal their gender and you should be able to identify the sex using the tips to follow. Once the plants go into full flower (8 to 10 weeks on average, for a natural outdoor grow) the differences between male and female plants will be glaringly obvious. We’ll talk more about exactly what each sex looks like in a moment.
Other Common Differences Between Male and Female Cannabis Plants
For the most part, the average home grower wants female cannabis plants. The ladies are the ones that produce the fattest, most resinous and most potent flowers – aka buds. Male cannabis plants are only desirable if someone wants to breed cannabis and save seeds (which is a whole other topic for another day). Even then, the grower will want to spot the difference between the male and female plants and separate them early on, unless they want free cross-breeding and pollination between many types of stains.
If you are growing from feminized seeds, you shouldn’t need to worry about sexing your cannabis plants all that much. While not 100% guaranteed, there is only a very slim chance that a feminized seed will produce a male plant. About 1% in fact. In all of our years growing, we have never had a cannabis plant grown from feminized seed turn out to be a male – though we only grow a handful of plants per year. Folks who grow hundreds of plants could potentially end with a rare male now and then.
Repeated colloidal silver treatments cause repression of the plant’s ethylene, which is the stuff that creates male flowers. Instead, the treated female plant will grow pollen sacks full of FEMALE pollen (XX rather than XY). Then breeders use the female pollen to pollinate female flowers, resulting in the development of all-female seeds.
Until we can tell the sex for sure, we continue to treat the plants equally. We start our seeds in small 4-inch nursery pots. About two weeks after germination, we pot the seedlings up into an approximately two-gallon (trade size) “sexing pot” like these BPA-free nursery pots. This enables everyone to continue to grow in a happy and healthy manner for several more weeks*. Then, once we can surely tell the difference between the male and female cannabis plants, only the ladies move into their forever home – 15 to 25 gallon grow bags full of recycled organic living soil. To learn more about our soil recipe and how we maintain it, see this article.