Autoflowering Weed Seeds & How Do They Flower?

Have you’ve ever shopped around for cannabis seeds, then you know that there are more than a few options available these days. More than ever before, breeders are offering autoflowering and feminized seeds. So what are autoflowering cannabis seeds and how do they work? Are they really worth the extra money?

What are autoflowering weed seeds?

Autoflowering seeds are cannabis seeds that begin to flower when the plant has reached a certain phase of development. This is opposed to photoperiod flowering, in which the plant begins to flower after the summer solstice. During the late summer and early autumn, red wavelengths of light from the sun become more abundant. This red light is packed with the energy the plant needs to develop complex flowers.

In the spring, blue light wavelengths are more predominant. Plants rely on this blue light to prosper during vegetative growth.

How do autoflowering weed seeds work?

As mentioned, photoperiod plants only begin to flower under certain light conditions. That is, they flower during a specific photoperiod, which is determined by the number of hours of sunlight versus the total number of hours in the dark.

To flower photoperiod plants early, most indoor growers put the plants on a strict 12/12 light schedule. Meaning 12 hours under the lights followed by 12 hours of complete darkness.

Autoflowering seeds work differently. Breeders have developed strains to begin flowering automatically when the plant reaches a certain size. As a result, most autoflowering plants are ready to harvest in under 10 weeks. Flowering often begins at a mere two to four weeks.

Autoflowering vs. standard seeds

Though there is variation from strain to strain, autoflowering strains tend to be much smaller than their standard counterparts.

As a result, yields from autoflowering plants tend to be slightly less. On the high end, some autoflowering cannabis seeds can yield up to 150 grams per plant, though the average is somewhere in the double digits. Autoflowering seeds are particularly useful in northern climates, which have extremely long summer days. Once the nights become long enough to trigger flowering, the rain and frost soon follow.

This means that many plants fail to develop full flowers before the cold arrives. Autoflowering cannabis seeds also have some advantage indoors, especially for those who love sativas. Autoflowering plants are generally small, compact, and can handle a wider range of grow environments.

Sativas, on the contrary, are tall plants with a long flowering period. Starting with autoflowering, sativa seeds makes it easier to grow these wily plants indoors. Most indica plants, however, are also short and perform well indoors regardless of whether or not you start with autoflowering seeds.

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[Updated, originally published 22.10. 2017]

  • Give your plants the best start, by purchasing seeds from  Zenpype seed store. We are offering a wide range of award winning feminized Sativa, Indica and Autoflowering seeds and we ship worldwide.
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