Pot Sizing

Choose by roots

Select a container only slightly wider than the healthy root mass. Moving a small root system into a much larger volume leaves wet mix beyond the roots and raises the risk of rot.

Routine step-up

For many small houseplants, increase the pot diameter by about 1 to 2 inches. Large plants may move up 2 to 4 inches. Slow-growing succulents often need less.

Drainage is mandatory

Use at least one unobstructed drainage hole. A decorative container without drainage may be used only as an outer cover pot; remove the inner pot for watering and let it drain completely.

Depth and shape

Shallow-rooted rosettes often suit broad, shallow pots. Deep or top-heavy plants need enough depth and weight for stability. Do not bury stems deeper merely to fill a tall pot.

When not to repot

Do not repot solely because the top looks crowded. Repot when roots circle densely, water runs around a shrunken root ball, growth is restricted, the mix has broken down, or the container is unsafe.

Sources

• Purdue Extension — Houseplants
• University of Maryland Extension — Repotting houseplants