Slow Growth in Banana Plants
Banana plants are supposed to grow fast. A healthy banana in warm conditions can produce a new leaf every 7 to 10 days. If growth has stalled or is noticeably slow, one or more environmental factors are limiting the plant.
Causes
Cold Temperatures
Growth slows dramatically below 60°F and stops below 50°F. If this is a seasonal slowdown in fall/winter, it is normal and growth will resume in spring. In cold climates, maximizing summer growing conditions is key.
Insufficient Light
Bananas need full sun. Plants in shade or indoors without supplemental light will grow slowly. See Sunlight Requirements.
Nutrient Deficiency
Bananas are very heavy feeders. A plant that is not being fertilized regularly will slow down. Nitrogen is the primary driver of vegetative growth. See Fertilizing.
Root Problems
Compacted soil, pot-bound roots in containers, or root rot restrict growth. If in a container, check whether the plant needs repotting.
Water Stress
Both under and overwatering slow growth. See Watering.
Overcrowding
Too many pups competing for the same rhizome's resources slow everyone down. See Pruning and Removing Pups.