How do I clone a cannabis plant?

Q: How do I clone a cannabis plant?

To clone cannabis, cut an 8–15 cm (3–6 in) shoot tip with 2–3 nodes from a healthy vegetative plant, cut below a node with a clean blade, dip it in IBA rooting gel and set it in a moist plug. Keep it at 22–26 °C (72–79 °F), 75–90% RH under gentle light of 50–150 µmol/m²/s. Most cuttings root in 7–14 days.

Short answer

Cut an 8–15 cm shoot tip with 2–3 nodes from a healthy vegetative plant, dip it in IBA rooting gel, set it in a moist plug, and hold it at 22–26 °C (72–79 °F), 75–90% RH and 50–150 µmol/m²/s. Most cannabis cuttings root in 7–14 days. Supported.

Why

Auxin speeds rooting. An IBA gel gave 2.1 times the rooting success of a willow-extract gel and better root quality ^[1]. In hemp, hormone-treated cuttings rooted far better than untreated ones ^[2].

Leaves feed the cutting. Three full leaves gave better roots than two, and trimming leaf tips cut rooting success from 71% to 53% ^[1].

Medium matters a great deal: in one trial rooting ranged from 13% to 80% across four media, with rockwool best ^[2].

Clean cutting, clean clone. Hop latent viroid spreads through infected cuttings and tools ^[3]. Where you cut also matters: cuttings can carry over the character of the branch they came from ^[4], so take them from consistent spots.

The numbers

Item	Target
Cutting	8–15 cm (3–6 in), 2–3 nodes, ≥ 3 full leaves
Medium temperature	22–26 °C (72–79 °F)
Humidity	75–90% RH under a vented dome
Light	50–150 µmol/m²/s, 18–24 h
Time to roots	7–14 days

What to do

Water the mother the day before. Sterilise the blade.
Cut 45° just below a node on a firm upper-to-mid shoot.
Drop the cut straight into water so air doesn't enter the stem.
Remove only the lowest leaves; keep at least three full leaves.
Dip in rooting gel from a small decanted portion, then stick in a pre-moistened plug.
Dome, vent daily, and keep gentle light on.

Common mistakes

Cuttings from a stressed, flowering or pest-ridden plant.
Double-dipping into the hormone stock.
Trimming every leaf in half.
Soggy plugs.
No labels: unnamed cuts get lost or renamed.

Full article: Clone-only cuts and how to preserve them
How long do clones take to root? · Do I need rooting hormone? · Best medium for rooting clones
Terms: cloning · cutting · mother plant

Follow-up questions

Should I clone before flowering?

Yes. Take cannabis clones before you flip a plant to flower, ideally from a healthy plant in mid-to-late veg. Vegetative cuttings root in about 7–14 days, while cuttings from flowering plants root slower, often 2–4 weeks, and must re-veg. Cloning every candidate before flowering is the simple way to keep a keeper you only identify after harvest.

Is it OK to rename a clone?

No. A clone is the same genotype as its source, so it should keep its original name and a written history of who it came from and when. Renaming known cuts is a big part of why one cut circulates under many names and why buyers can't tell what they have. If you don't know the name, say so, and record what you do know.

Do I need to trim the leaves on a cutting?

Usually not. In a controlled cannabis study, cutting off leaf tips reduced rooting success from 71% to 53%, and cuttings with three leaves had better roots than those with two. Keep at least three fully expanded, uncut leaves, remove only the lowest ones that would sit in the medium, and control water loss with humidity instead.

Sources

Caplan D, Stemeroff J, Dixon M, Zheng Y. 2018. Vegetative propagation of cannabis by stem cuttings: effects of leaf number, cutting position, rooting hormone, and leaf tip removal. Canadian Journal of Plant Science 98(5):1126-1132. doi.org/10.1139/cjps-2018-0038

Campbell SM, Anderson SL, Brym ZT, Pearson BJ, 2021. Evaluation of substrate composition and exogenous hormone application on vegetative propagule rooting success of essential oil hemp (Cannabis sativa L.). PLOS ONE 16(7): e0249160. doi.org/10.1371/journal.pone.0249160

Adkar-Purushothama CR, Sano T, Perreault JP. 2023. Hop latent viroid: a hidden threat to the cannabis industry. Viruses 15(3):681. doi.org/10.3390/v15030681

Olesen PO. 1978. On cyclophysis and topophysis. Silvae Genetica 27(5):173-178. thuenen.de/media/institute/fg/PDF/Silvae_Genetica/1978/Vol._