The yucca variety most commonly enjoyed indoors is spineless yucca, or Yucca elephantipes. These Mexican natives accommodate most demands imposed by their human keepers. They're attractive, pest and disease resistant, and ask little in the way of maintenance. Yuccas tolerate a wide range of lighting conditions, and even clean the air of indoor environments. Their biggest pet peeve is likely to be inappropriate watering. Some may feel that this yucca is too fussy about improper watering practices. But over-watering is the most common cause of demise of indoor specimens, as elephantipes is a desert dweller by nature.
Provide your indoor yucca plant with as much direct sun as possible. Place it in the brightest spot available, with southeastern and southwestern exposures being best. These plants like at least several hours of direct sun daily, but can tolerate indoor home and office lighting when maintained properly.
Maintain temperatures between 50 and 80 degrees F for your indoor yucca. Extreme temporary temperature fluctuations typical in homes and offices can be tolerated. Set it outside on warm, sunny days whenever frost isn't expected. Elephantipes won't survive freezing weather. Cold hardy only in zones 9b to 11, it prefers 50 to 60 degree F wintertime temperatures.
Moisten the soil surface evenly April through September, allowing it to completely dry out before watering again. Let the top 1 inch of medium dry out between wintertime waterings. Excellent drainage is crucial, so maintain the plant in a clay container to facilitate maximum drainage while stabilizing top-heavy specimens.
Feed a good all-purpose, water soluble houseplant fertilizer once monthly April through September to healthy, actively growing yucca plants.
Use clean, sharp pruning shears to remove spent flower stalks when the blooms have faded. Cut the stalk off about 3 to 5 inches above the point where it joins the main stem. Cut away any dead foliage whenever necessary.
Prune your indoor yucca early in March, right before it enters the growing cycle if it has grown too tall. Use sharp loppers or a saw to cut up to half of the top of the stalk off just prior to the next watering. Provide the plant with as much direct sunlight as possible to help it recover from pruning stress, and it will soon produce new foliage. Water slightly less because the plant is smaller now.