What does a healthy cannabis clone look like?

Leaf color and texture

Healthy clone leaves are uniformly bright green with no irregular spotting, browning at the tips, or yellow patches. The leaves should look fully expanded and hydrated — slight stiffness when touched, not limp. Yellowing across the entire leaf usually indicates nitrogen deficiency or environmental stress; brown leaf tips suggest nutrient burn or low humidity. Brown spots can indicate fungal disease (especially in high-humidity environments) or pest damage. The leaves on a clone may not be perfect — small physical scuffs from packaging are fine — but uniform color across the leaf surface is the key signal.

Stem condition

A healthy clone's stem is firm and springy when gently flexed between thumb and forefinger. It should bounce back to its original position. A limp, droopy stem indicates either dehydration (most common) or root rot at the base. A hollow-feeling stem can suggest fungal disease in the vascular tissue. The base of the cutting where it enters the rooting medium should be clean and uniform in color, not browning or rotted.

Root development

For rooted clones, white root tips should be visible at the bottom of the rooting medium. The roots should be bright white — brown roots indicate root rot from overwatering or poor oxygenation, and black roots indicate severe rot that may not be recoverable. You should see at least 3-5 distinct root tips emerging by day 14 post-cutting. If no roots are visible by day 21, the clone has likely failed to establish.

New growth

Within 5-10 days of rooting, you should see fresh new growth emerging from the apex of the cutting. New growth will be smaller and lighter green than the original leaves — that's a normal sign of active vegetative development. Lack of new growth after 14 days usually means the clone has rooted but is locked out of nutrients in its rooting medium and needs to be transplanted or fed a light nutrient solution to break through the stall.

Pest and disease checks

Inspect the underside of every leaf for spider mites (tiny moving dots, fine webbing), russet mites (look for yellowing and rough leaf texture; mites themselves are too small to see without magnification), aphids (small green insects clustered on stems), or thrips (silvery streaks on leaves). White powdery residue on leaves indicates powdery mildew. Any sign of pests or disease on a fresh clone should be addressed immediately — do not bring it into a clean grow space until it's been quarantined and treated.