Tall leggy plants reaching for the sky can ruin an otherwise beautiful display of foliage and color unless, of course, your goal is to create a visual image of starkness. Returning those stretched out plants to their natural shape and size takes more than chopping off the top--although that may be part of the remedy. Leggy plants can be changed to dense-compact plants with a little care and time to make adjustment.
Examine the plant for any signs or insect damage or disease that may threaten its overall health. Look under leaves for tiny insects or chew holes. Examine the soil for mold or mossy growth. Although the presence of insects rarely cause legginess in plants, the stress your plant is experiencing makes it more susceptible to disease carried by insects.
Treat any underlying conditions. Use herbicides--following the directions on the label--to control insects and re-pot in new soil if mold or moss is present.
Pinch out the center leaves on all branches by squeezing new leaves between your thumb and forefinger to pinch them from the plant. This forces new growth to appear along the stem and encourages dense foliage.
Move the plant to appropriate lighting. Plants grow tall and leggy with thin spindly stems in an effort to reach the light. Check the lighting requirements for your specific plant and match them as closely as possible.
Increase light for houseplants by placing plants closer to windows or opening curtains and shades to allow more light into the room. Supplemental lighting from plant lights may be needed in dark corners, particularly in winter when light levels are low. Some plants thrive with ordinary fluorescent lights.