Autoflower care & feeding by week
Autoflowers run on AGE, not light schedule — every stressed day is gone forever. This is the compressed-clock schedule our coach uses for auto-flagged plants.
| Week | Stage | Care |
|---|---|---|
| Week 1 | Germination → seedling | Plain water only. High humidity (65-80%), gentle light. Do not transplant autos if avoidable — start in the final pot. |
| Week 2-3 | Early vegetative | First light feeding at ~25% strength once true leaves multiply. VPD 0.8-1.0 kPa. No topping yet; LST only if vigorous. |
| Week 4-5 | Pre-flower (autos flip on age, not light) | Full vegetative feeding. Gentle low-stress training only — recovery time is yield you never get back on a compressed clock. |
| Week 6-8 | Flowering | Transition to bloom nutrients. VPD 1.0-1.4 kPa, RH down to 40-55%. No high-stress training, period. |
| Week 9-11 | Ripening & flush | Watch trichomes, not the calendar — autos finish on their own schedule. Reduce feed; many growers flush the final 7-10 days. |
The three autoflower rules
1) Never transplant if you can avoid it — start in the final pot. 2) Train gently and early or not at all. 3) Harvest windows are cultivar-specific; judge by trichomes, not by breeder week counts.
Common questions
Do autoflowers need a light schedule change?
No. Autoflowers flower on age rather than day length, so growers typically run one schedule — often 18/6 or 20/4 — from seed to harvest.
Can I train an autoflower?
Gently and early. Autos cannot recover lost time in veg the way a photoperiod plant can, so low-stress training beats topping.
Why did my auto finish smaller than advertised?
Autos punish setbacks. Transplant shock, a pH excursion or a week of poor light in early growth cannot be recovered later, because flowering starts on schedule regardless.
- Fabric pots (3–5 gal) — autos hate transplanting — start in the final pot
- Hygrometer / thermometer — autos punish environment drift because they never pause to recover
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Keep reading
- Stage-by-stage environment targets
- 18/6 vs 20/4 for autos
- Judging harvest by trichomes, not the calendar
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