How Long Does It Take to Grow Weed? Seed to Harvest Timeline for Canada

Last updated: October 2026

The honest answer to how long weed takes to grow is that it depends on three choices you make before the seed is even wet: the seed type, whether you grow indoors or outside, and how big you want the plant to get. A small autoflower in a tent can go from seed to jar in under four months. A big outdoor photoperiod plant in Ontario takes most of the year once you count the spring start and the autumn cure.

This guide breaks the whole process into stages with realistic week counts, then lays out a Canadian calendar for each region, from the BC coast to the Prairies and the Atlantic provinces. It also covers the step most timelines leave out: the drying and curing weeks between harvest and a smokeable bud. Use the tables to plan your first germination date backwards from the harvest you want.

How long does it take to grow weed from seed to harvest?

From seed to harvest, a photoperiod cannabis plant takes roughly 12 to 20 weeks indoors and 20 to 24 weeks outdoors in Canada, while an autoflower takes 9 to 12 weeks wherever you grow it. The biggest variable indoors is the vegetative stage, which you control with the light. Outdoors, the sun decides: plants flower when the nights get long enough in late July and August, whatever date you planted.

The table below shows typical ranges for each stage. Short ranges belong to compact indica leaning strains and small plants; long ranges belong to sativas, hazes and growers who veg big plants.

Those totals assume a healthy plant. Stress from overwatering, cold roots or a nutrient problem in the first month can add one to two weeks, mostly by slowing the seedling stage.

What are the stages of cannabis growth, week by week?

Cannabis grows in four stages, germination, seedling, vegetative and flowering, followed by two post-harvest stages, drying and curing. Here is what happens in each one and how long it lasts.

1. Germination: 1 to 7 days

The seed absorbs water, cracks and pushes out a white taproot. With the cup of water and paper towel method most fresh seeds show a root in 24 to 72 hours; older or harder seeds can take up to a week. Plant the seed root down about 1 cm deep as soon as the taproot is 0.5 to 2 cm long. Our germination guide walks through the method step by step.

2. Seedling: weeks 1 to 3

The first rounded leaves (cotyledons) open, followed by the first true leaves with one blade, then three, then five. Growth looks slow above ground because the plant is building roots. Keep the medium moist but never soggy, the temperature at 22 to 26 degrees and humidity around 60% to 70%. A seedling is ready to move on when it has four or five sets of true leaves and the newest leaves show the full number of blades for the strain.

3. Vegetative growth: weeks 3 to 10

This is the growth spurt. The plant adds new nodes every few days, thickens its stem and can double in size in a week once roots fill the pot. Indoors, photoperiod plants stay in veg as long as they get 18 or more hours of light a day, so you choose the length: three to four weeks for a small plant in a tent, six to eight weeks for a large one. This is also the window for topping and training. Outdoors in Canada, veg runs from planting out in late May until the plant starts flowering in late July or early August.

4. Flowering: weeks 8 to 11 of bloom

Flowering starts indoors when you switch the light to 12 hours on and 12 hours off, and outdoors when the nights lengthen. The first two to three weeks bring the stretch, when plants grow 50% to 100% taller and white pistils appear at the nodes. Weeks four to six are bud building. In the last two to three weeks the buds swell, pistils darken and trichomes turn from clear to cloudy to amber. The breeder or seed bank flowering time is the best guide: a strain listed at 8 to 9 weeks will usually be ready between day 56 and day 65 after the switch.

5. Drying: 7 to 14 days

After harvest, branches hang in a dark room at about 18 to 21 degrees and 55% to 62% humidity. Buds are dry enough when small stems snap rather than bend. Rushing this step with heat is the most common way to ruin the flavour of a good harvest.

6. Curing: 2 to 8 weeks

Dried buds go into sealed glass jars, opened daily for the first week to release moisture, then less often. Two weeks is the minimum for a smooth smoke; four to eight weeks brings out the full aroma. Curing is why seed to smokeable bud always takes longer than seed to harvest.

How long do autoflowers take compared with photoperiod plants?

Autoflowers are the quickest option, finishing 9 to 12 weeks after germination because they flower on an internal clock instead of waiting for longer nights. Most autoflowers start flowering around week three or four, whatever the light schedule, and finish their bloom five to seven weeks later. Photoperiod plants take longer because the vegetative stage has no fixed end, but they grow bigger, yield more per plant and can be kept in veg to recover from problems.

A third option sits in between. Fast version seeds are photoperiod plants with a small amount of autoflower genetics bred in, which cuts one to two weeks from the bloom. You still control veg with the light, but the plant finishes earlier. A chocolate indica such as Afghan Chocolope Fast Version, for example, flowers in 7 to 8 weeks and is usually ready outdoors by mid September.

How long does it take to grow weed indoors?

Indoors, most growers harvest a photoperiod plant 3 to 4 months after germination and an autoflower about 2.5 to 3 months after. The schedule is predictable because you control light, temperature and the switch to flowering. A common first-grow plan looks like this:

1. Days 1 to 5: germinate in a paper towel and plant the sprouted seed.
2. Weeks 1 to 3: seedling stage under gentle light, 18 hours on and 6 off.
3. Weeks 3 to 7: vegetative growth, topping once around week four and spreading branches.
4. Week 7: switch to 12 hours on and 12 off when plants reach about half the final height you can fit.
5. Weeks 7 to 16: flowering, usually 8 to 9 weeks for a modern hybrid.
6. Weeks 16 to 18: harvest, then dry for 10 to 14 days.
7. Weeks 18 to 22: cure in jars; the first buds are ready to smoke around week 20.

With one tent and photoperiod strains, that rhythm gives about three harvests a year. Autoflowers allow four, or even five with a staggered start. Running two small tents, one in veg and one in bloom, lifts that to five or six photoperiod harvests a year.

How long does it take to grow weed outside in Canada?

Outdoors in Canada, a photoperiod plant takes 5 to 6 months from an indoor spring start to an autumn harvest, because flowering is set by day length rather than by the date you planted. Around the summer solstice, southern Canada gets roughly 15.5 to 17 hours of daylight depending on latitude. Plants keep growing until nights lengthen enough to trigger flowering, which typically happens from late July to early August, and most strains then need 8 to 10 weeks to finish.

That makes the harvest date a function of the strain’s flowering time and your first autumn frost. The table gives a realistic calendar for each region, assuming seeds are started indoors and moved outside after the last frost. For more detail on plant-out dates, see when to plant cannabis outdoors in Canada.

Two provincial rules change the plan. Quebec does not allow home cultivation at all, and Manitoba has allowed up to four plants per household since May 2025, but indoors only. Everywhere else, the federal limit of four plants per household applies, as Health Canada explains in its guide to growing cannabis at home safely. With only four plants, a missed harvest window costs a large share of the year, so strain choice matters more than it does for a commercial grower.

Short seasons: the Prairies, the North and the Atlantic

Where the first hard frost can arrive in mid to late September, choose strains that finish in 7 to 9 weeks of bloom, or autoflowers planted in late May for an August harvest. A 10 week sativa planted in Saskatchewan will usually still be flowering when the frost arrives. The guide to fast flowering seeds for Canada lists strains that fit those windows.

Long, wet autumns: the BC coast and the Maritimes

Here the limit is rain, not frost. Dense buds that are still finishing in mid October are at risk of mould, so a strain that finishes by early October, a rain cover over the last two weeks, or a greenhouse all buy time.

Can you make weed grow faster?

Yes, but only by choosing the right seed and avoiding delays; no fertilizer or trick shortens a strain’s genetic flowering time. These steps make the biggest difference to the total timeline:

1. Pick the seed type for your deadline. Autoflowers and fast version seeds save four to eight weeks compared with a standard photoperiod.
2. Shorten veg indoors. Flipping to 12/12 after three weeks instead of six saves three weeks, at the cost of a smaller plant and yield.
3. Use fresh, viable seed. A seed that cracks in 24 hours gets a three to five day head start on one that takes a week.
4. Avoid transplant shock. Start autoflowers in their final pot; move photoperiods once, gently, when roots reach the edges.
5. Keep conditions steady. Cold roots below 18 degrees, overwatering and pH swings each stall growth for days at a time.
6. Harvest on trichomes, not on hope. Cutting early saves a week but costs weight and potency; it is the one shortcut not worth taking.

How do you know when weed is ready to harvest?

Weed is ready to harvest when most of the trichomes on the buds have turned from clear to cloudy, with a small share of amber, usually close to the end of the strain’s listed flowering time. Pistils are a rough guide: most will have darkened and curled in. A jeweller’s loupe or a cheap clip-on phone microscope shows the trichome colour clearly.

• Mostly clear: not ready; potency and weight are still building.
• Mostly cloudy, a few amber: peak for a bright, clear effect.
• Cloudy with 10% to 20% amber: a heavier, more relaxing result.

Check buds near the top of the plant and a few lower down, since the top colas often ripen several days earlier. Outdoors in Canada, keep an eye on the forecast too: a frost or a week of heavy rain can make it worth harvesting a few days before the ideal point.

How long from harvest until you can smoke it?

Plan on three to six weeks between cutting a plant and smoking a properly cured bud. Drying takes 7 to 14 days, and curing adds at least two more weeks. You can technically smoke a bud once it is dry, but it will taste harsh and grassy because chlorophyll and moisture are still breaking down.

A slow dry and cure also protects your harvest. Buds jarred too wet can grow mould in days, while buds dried too fast in warm air lose much of their terpene content. If you grew four plants, those six weeks decide whether the jar tastes like the strain description or like hay.

Seeds that suit a tight timeline

• Afghan Chocolope Fast Version: a 7 to 8 week photoperiod that finishes by mid September outdoors.
• Candy Fumez: an 8 to 9 week hybrid with a late September finish across most of Canada.

Frequently asked questions

How many months does it take to grow weed?

It usually takes 3 to 5 months to grow weed indoors from seed to harvest and 5 to 6 months outdoors in Canada. Autoflowers are quicker at about 2.5 to 3 months. Add one to one and a half months for drying and curing before the buds are ready to smoke.

How long does it take to grow weed from seed to smoke?

From seed to smoke, plan on about 4 to 6 months indoors and 6 to 7 months for an outdoor plant in Canada. That includes germination, seedling, vegetative growth, flowering, a 7 to 14 day dry and at least two weeks of curing in jars.

How long does it take to grow weed in a tent?

In a tent, photoperiod plants usually take 14 to 18 weeks from seed to harvest, with 3 to 6 weeks of veg and 8 to 10 weeks of flowering. Autoflowers in a tent take 9 to 12 weeks. With one tent, that allows about three photoperiod or four autoflower harvests a year.

How long does it take to grow weed outside in Canada?

Outside in Canada, most photoperiod plants take 5 to 6 months: start seeds indoors in April, plant out in late May or early June, and harvest from mid September to early October. Autoflowers planted outside in late May are usually ready in August.

How long do weed seeds take to germinate?

Most fresh cannabis seeds germinate in 24 to 72 hours with the paper towel method, and nearly all viable seeds show a taproot within 7 days. Seedlings usually break through the soil 2 to 5 days after planting.

Every seed we sell is already in Canada and ships from Vancouver in 3 to 7 business days, so your timeline starts the week you order. If speed matters most, browse our autoflowering seeds.