A well ripened cannabis seed had sufficient time for hardening its shell. Healthy cannabis seeds are therefore provided with a hard smooth skin without cracks. You can test the hardness of the shell by taking the seed between your fingers and applying gentle pressure. Immature seeds will easily crack or crumble while qualitative cannabis seeds won’t damage.
Healthy cannabis seeds are sufficiently matured and therefore have a different appearance than unripened cannabis seeds. For example, viable cannabis seeds meet a number of criteria. Think of the size and shape, hardness of the outside and color.
Note: the moisture from your fingers can damage the seed. Please use linen gloves to prevent this.
Shape and size of a cannabis seed
Cannabis seeds have a unique shape. They are oval, have the shape of a drop and are small in size. On average, a cannabis seed is about 2 to 5 mm long and 2 to 3 mm thick. If you want to know what you can expect in advance, then we can advise you to take a look at the seeds of a tomato.
Although it isn’t always visible with the blind eye, on a quality cannabis seed you can see a pattern of “tiger stripes” or dark spots.
To test the viability of a seed you can place the seed in a glass with distilled water. Seeds that sink within 2 hours have sufficient mass. These seeds generally have a better chance of sprouting than seeds that still float.
Curious how healthy cannabis seeds look? Continue reading!
A quick web search will bring up all kinds of myths about how to tell female cannabis seeds from males. One of the most popular ones comes from a chart showing 5 different seeds that claims that the female seeds have “a perfectly round volcano-like depression at the bottom (from where the seed was attached to the plant).”
The alternative to this is to risk buying seeds from a hobbyist. This isn’t to say that hobby growers cannot produce fantastic genetics, but if you don’t know them or their skills, there’s no way to know whether your seeds will grow.
We do not recommend taking the size or shape of a seed into consideration as a sign of its quality. Some strains simply produce smaller seeds than others, and sometimes the same plant can produce seeds of different sizes and shapes. Never discard a seed just because it is smaller or of a different shape than another one.
Germinating All Your Seeds Regardless
However, slight patience is required when conducting the float test, as results are not immediately apparent. You’ll have to wait for approximately 1–2 hours before confirming the results. Some good-quality seeds will need adequate time to absorb enough water for them to sink. Use this time to go water the garden and get some much needed pruning done. Upon your return, any seeds that remain on the surface are most likely not viable and won’t be worth further time and effort.
Remember, just like animals and other living things, cannabis seeds are biologically different from one another (even if they are technically the same strain) and therefore will exhibit different physical characteristics. Don’t let these natural differences fool you into thinking that a larger, rounder, and darker seed (for example) is of better quality than a lighter, smaller, and more oval-shaped one.
If you are still unsure about the quality of your seeds after analysing their appearance and toughness, it’s time to put your lab coat and goggles on. Well, not quite. This test is extremely easy and only has two possible outcomes. Fill up a drinking glass or glass jar with water (preferably spring or distilled) and place your seeds on the surface.
Mature cannabis seeds usually have a hard outer shell that can vary in color from very dark (or almost black) to very light grey and may have tiger-like stripes. You should be able to firmly press these seeds between your fingers without damaging them.