The question underneath most first-grow anxiety is simply "what's supposed to be happening right now?" This is the whole grow laid out week by week — what the plant is doing, what you should be doing, what it needs, and the buy-it-before-you-need-it list at each stage — for a photoperiod plant, with the autoflower differences noted where they matter.
The overview
| Stage | Photoperiod | Autoflower | Light | What the plant wants |
|---|---|---|---|---|
| Germination | 2–7 days | 2–7 days | None, or dim | Warmth, moisture, darkness |
| Seedling | 2–3 weeks | 2 weeks | 18/6, 200–400 PPFD | Humidity, gentle everything |
| Veg | 3–8 weeks (your call) | 2–3 weeks (automatic) | 18/6, 400–600 PPFD | Nitrogen, training, room to grow |
| Transition / stretch | Weeks 1–3 of 12/12 | Weeks 4–5 from seed | 12/12 (photo) · 18/6 (auto), 600–800 PPFD | Still some N, support |
| Flower | Weeks 3–8 of 12/12 | Weeks 6–10 | 700–1000 PPFD | P and K, lower humidity, airflow |
| Ripening | Weeks 8–10 of 12/12 | Weeks 10–12 | Same, maybe dimmed slightly | Flush, cool nights, 35–40% RH |
| Dry | 7–14 days | 7–14 days | Dark | 60 °F / 60% |
| Cure | 2–8 weeks | 2–8 weeks | Dark | 62% in jars |
| Total | 4–6 months | ~3 months |
Germination (days 1–7)
Paper towel between two plates, damp not wet, somewhere around 75–80 °F. A taproot in 1–4 days; plant it half an inch deep, root down, in a moist starter cup or — for autos — the final 3-gallon pot. Cover with a clear cup for humidity. First leaves in 2–5 days more. Don't feed. Don't fuss.
Have ready: seeds, a starter cup or the final pot, potting mix, a spray bottle.
Seedling (weeks 1–3)
Two rounded leaves, then the first serrated true leaves, then a new node every few days. Light at 30–40% or hung high; 200–400 PPFD is plenty and more just stresses it. Humidity 65–70% — a dome or a humidifier for the first week. Water around the seedling, a little, and let it dry between. The number one seedling killer is love: too much water, too much light, too much feed.
Plain water in soil for the first two weeks; quarter-strength feed with cal-mag in coco.
Have ready: thermometer-hygrometer, a clip fan on low, a humidity dome or spray bottle, pH pen.
Veg (photoperiods: weeks 3–10; autos: weeks 3–4)
The plant builds its frame. Nitrogen-heavy feed, building to full strength. The light comes up to 400–600 PPFD. This is when training happens: top at the 4th–6th node (photoperiods only), start tying down, install a net if you're using one. Transplant photoperiods up to their final 5-gallon pot when roots reach the sides of the current one.
For photoperiods, veg lasts as long as you want. The rule of thumb: flip when the plant is half the height you want it to finish at, because it'll roughly double. In a 6-ft tent with 5-gallon pots, that's usually around 18–24 inches tall, 4–6 weeks of veg.
Autos veg themselves for about three weeks and then start flowering. You'll see pre-flowers (tiny white pistils at the nodes) around week 3–4. Nothing to do but not interfere.
Have ready: veg nutrients, cal-mag, ties, stakes or net, 5-gallon pots and mix for the transplant, EC meter.
The flip and the stretch (photoperiods: 12/12 weeks 1–3; autos: weeks 4–5)
Switch the timer to 12/12. Over the next two to three weeks the plant stretches — 1.5× to 3× depending on strain — while pistils appear at every node. Keep it tied down and tucked under the net, keep some nitrogen in the feed (switch to bloom over a week or two, not overnight), and raise the light as it comes up. Humidity down to 45–50%.
The dark period now has to be dark. Check the tent for leaks. Interrupting it causes stress, hermaphrodite flowers, and in the worst case a return to veg.
Have ready: bloom nutrients, more ties, and the carbon filter installed — the smell starts now.
Flower (12/12 weeks 3–8; autos weeks 6–10)
The stretch stops and the buds form and fatten. Full bloom feed, peak strength — this is the hungriest the plant will be. Light to full intensity, 700–1000 PPFD. Humidity 40–45%, temperature 68–78 °F, and the clip fan moving air through the canopy. One last light defoliation around day 21; then hands off.
Trichomes are forming: from around week 6 you can start checking them with a loupe, if only to learn what "not ready" looks like.
Have ready: loupe, a dehumidifier if your climate needs it, humidity packs and jars for the end.
Ripening (12/12 weeks 8–10; autos weeks 10–12)
Feed tapers, then the flush: plain pH'd water for the last 1–2 weeks. Fan leaves yellow and drop; that's right. Humidity to 35–40%, nights cooler. Check the big buds for rot every few days. Loupe the buds — not the leaves — every few days, and harvest at mostly cloudy trichomes with 10–20% amber. The full method is in When to harvest. Cut in the morning.
Drying and curing (2 weeks + 4 weeks)
Hang the branches at 60 °F / 60% in the dark with gentle air for 7–14 days, until small stems snap. Trim, jar at two-thirds full with a 62% pack, burp daily for a week and then weekly. It's good at two weeks, better at four, done by eight. The detail is in Drying and curing.
Realistic yields
Under a good LED, a rough planning figure is 0.75–1.25 g per watt of actual light for a competent grow — so 3–4 oz from a 100 W 2×2, 8–12 oz from a 250 W 2×4, and a pound or more from a 450 W 4×4 with four well-trained photoperiods. A first grow usually lands at the low end; the third grow at the high end. Autos yield less per plant but you run more of them.
Where people lose time
- Starting an auto in a small cup and transplanting. Costs it a week it doesn't have.
- Vegging a photoperiod too long in a short tent, then fighting the stretch.
- Flipping to bloom nutrients overnight. The stretch still wants nitrogen.
- Harvesting on the packet date. Two weeks early is 15–20% of the yield and most of the potency.
- Rushing the dry. Four months of work, ruined in three days in a warm room.
Plan the kit for it
The setup planner sizes the light, fan, filter and pots for your tent and seed type; the beginner checklist is the complete shopping list in order. Between them and this timeline, the first grow is a matter of patience rather than knowledge.
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