Do autoflowers yield less than photoperiod plants?

Modern autoflowers from reputable breeders can yield 100–400g per plant indoors, approaching many photoperiod strains. However, in optimal conditions (large containers, high PPFD, advanced feed schedule), photoperiod plants still generally outperform autos by 30–60% in raw yield per plant. The trade-off is a faster cycle and simpler light schedule with autos.

Can autoflowers be cloned?

Technically yes, but it is not practical. Autoflowers flower based on age, not light. A clone taken from an autoflower will be the same biological age as the mother, meaning it will enter flowering almost immediately after rooting with almost no vegetative growth. The result is a tiny, low-yielding plant. Cloning photoperiod strains is far more effective.

What light schedule is best for autoflowers?

Most growers run autoflowers at 18–20 hours of light per day throughout the entire cycle. Unlike photoperiod strains, autos do not need a 12/12 light schedule to flower. Some growers use 20/4 or even 24/0 to maximise yield, but 18/6 is a good balance of growth and energy cost.

Autoflower vs Photoperiod Cannabis: Which Should You Grow?

By Photon Flux Nutrients — Updated April 2026 — 10 min read

The choice between autoflowering and photoperiod cannabis seeds is one of the first decisions every grower faces. Both have real strengths and meaningful limitations. This guide gives you a direct, data-driven comparison so you can match your seed type to your actual goals, setup, and experience level.

1. How They Differ Biologically

Photoperiod strains flower when the light cycle drops to 12 hours of light per day (or less). In nature, this happens as days shorten in late summer. Indoors, the grower controls flowering entirely by switching the timer. This gives full control over vegetative size before flowering begins.

Autoflowering strains contain genetics from Cannabis ruderalis, a subspecies adapted to short summer seasons in Northern Europe and Central Asia. Autos flower based on age — typically 3–5 weeks from germination — regardless of the light schedule. They complete their entire cycle in 70–90 days.

2. Side-by-Side Comparison

Factor	Autoflower	Photoperiod
Total cycle	70–90 days	100–160+ days
Light schedule	18–20h all cycle	18h veg / 12h flower
Yield per plant (indoor)	50–400g	100–600g+
Yield per m²	300–500g	400–700g+ (skilled)
Clonable	No (impractical)	Yes
Mother plants	No	Yes
Sensitivity to mistakes	Higher (no recovery time)	Lower (can extend veg)
Container size	7–15L optimal	15–50L+
CO₂ enrichment impact	Moderate	High
Training (LST/SCROG)	Limited (gentle LST only)	Full range
Seed cost	Medium	Low–High (feminised)
Energy cost per gram	Lower	Varies (longer cycle)

3. When to Choose Autoflowers

Autoflowers make most sense when speed, simplicity, or multiple harvests per year are priorities. Key scenarios:

Beginner growers who want to complete a full cycle quickly and learn from each run
Small tent setups (60×60cm to 80×80cm) where plant size must stay compact
Outdoor growing in northern climates where the season is too short for photoperiods to finish before frost
Multiple harvests per year — 4–5 autoflower runs fit in the time of 2–3 photoperiod runs
Stealth grows where smaller, faster plants reduce exposure risk

4. When to Choose Photoperiods

Photoperiod strains offer greater yields, more training options, and the ability to maintain mother plants. They are the commercial standard for good reason:

Commercial or semi-commercial production where maximising yield per watt matters
Cuttings and cloning — run one mother plant and clone indefinitely to maintain a proven genetic
Advanced training methods (SCROG, SOG, mainlining, topping) that require weeks of vegetative recovery time
CO₂ enrichment — photoperiods respond more strongly to elevated CO₂ because they can be held in veg longer
Large containers and high-yield targets — photoperiods scale better with pot size

5. Feeding Differences

Autoflowers are generally more sensitive to high EC levels and nutrient burn than photoperiods. Start EC lower and increase gradually:

Phase	Autoflower EC	Photoperiod EC
Seedling	0.4–0.6	0.4–0.8
Vegetative	0.8–1.4	1.2–2.0
Flowering	1.4–2.0	2.0–3.0
Flush	0–0.2	0–0.2

pH targets are the same for both types: 5.5–6.2 in coco/hydro, 6.0–7.0 in soil. See our cannabis nutrient schedule guide for a full week-by-week breakdown.

6. Verdict by Grower Profile

Grower Profile	Recommended	Reason
First-time grower	Autoflower	Fast feedback loop, no light schedule management
Small tent, 1–4 plants	Autoflower	Compact size, 18h light simplicity
Commercial producer	Photoperiod	Higher yield, clonable, scalable
Outdoor, short season	Autoflower	Finishes before frost, light-independent
Wants to clone or breed	Photoperiod	Cloning and mother plants require photoperiod genetics
Intermediate, maximising yield	Photoperiod	SCROG, CO₂, high EC — all scale better

The short answer: start with autoflowers to learn, graduate to photoperiods when you are ready to optimise yield and maintain consistent genetics.