45 Day Autoflower Seeds

What Are 45 Day Autoflower Seeds?

These are autoflowering strains selected for short listed flowering periods. A flowering period starts later than germination, so it is shorter than the full seed-to-harvest lifecycle.

Many of the autos shown here are listed in the 6–8 week flowering range. Total seed-to-harvest time can be longer because flowering time is not the same as the plant's full lifecycle.

Like other autoflowering seeds, they begin flowering as they mature rather than waiting for a change in the light schedule.

How to Choose 45 Day Autoflower Seeds

Speed has already narrowed the range. Choose by the finish time you need, the space you have and the balance of yield, THC and flavor you want.

Start with timing. A 6–8 week flowering label does not necessarily mean harvest in 6–8 weeks from seed. If a firm deadline matters, favor strains with a stated seed-to-harvest estimate as well as a short flowering period.

Next, match the plant to your space. Short autos are the natural starting point for limited indoor height; medium plants give you more room to consider yield. Outdoors, a quicker lifecycle can be useful in a shorter season, provided the variety suits your conditions.

Then choose the trade-off that matters most. A compact, moderate-THC auto may suit a small setup, while a higher-yielding or more potent option may be worth a little more space or time. Compare indoor yields on the same g/m² basis, and treat breeder figures as estimates rather than a guaranteed harvest.

Once timing and size fit, use THC, expected yield, flavor, breeder, pack size and price to make the final choice. If strength is your priority, the high THC autoflowers category offers a broader selection than speed alone.

Some fast autos have moderate THC levels, while others in this category are listed above 25%. Their listed effects are useful descriptions, though an individual's experience can vary.

Do Faster Autoflowers Mean Lower THC or Smaller Yields?

The 45 day autoflower range at 420 Seeds covers very different THC and yield levels. Some strains sit in a moderate THC range, while others are listed above 25%. Expected indoor yields range from compact plants with smaller harvests to options listed at 500–600g/m² or more. Speed does not set a fixed ceiling for either trait.

If harvest size matters just as much, compare our high yielding autoflowers. You can prioritize a fast finish while still choosing a yield range that suits your setup.

Compare 45 Day Autoflower Seeds at 420 Seeds

Two strains can share a listed 6–8 week flowering band and still offer different strengths and yields.

For example, Wedding Cake Autoflower by 420 Seeds is listed at 18–20% THC and 400–500g/m², while Gorilla Glue Autoflower by MSNL Seeds is listed at 20–24% THC and 500–600g/m². Both currently show a 6–8 week flowering band in this category. Those figures make the trade-off more useful than the category name alone.

Are 45 Day Autoflower Seeds Right for You?

They can suit growers with a shorter outdoor season, anyone who wants a quicker indoor turnaround, or buyers who simply prefer shorter grow cycles. The shorter timing is the appeal; plant height, yield and THC still leave plenty of room to choose.

If you are happy to wait longer for a particular flavor, plant size or yield, the wider autoflower seed range gives you more choice.

If location matters more than speed, compare indoor autoflowers or outdoor autoflowers.

Why Buy 45 Day Autoflower Seeds From 420 Seeds?

420 Seeds brings together fast autos from its own range and established breeders, so you can compare flowering time, size, THC, yield and pack price in one place.

45 Day Autoflower Seeds FAQs

Do 45 day autoflowers really finish in 45 days?

No. The name points to a fast-flowering category; it does not mean that every plant is ready 45 days from seed. A listed flowering period and a full seed-to-harvest estimate describe different stages of the grow.

Can 45 day autoflowers have high THC?

Yes. Some strains in the category are listed above 25% THC, while others offer more moderate levels. A fast flowering band does not by itself determine potency.