Growing Conditions

• Yucca plants prefer well-draining soils and do not tolerate damp conditions. Too much water renders the plant susceptible to root rot. Avoid overhead irrigation systems, and ensure plant foliage is well aerated and able to dry out before the next round of wet weather. Wet foliage is prone to leaf spot, a fungus-borne disease detrimental to yucca bud health and flower appearance. Leaf spot and fungal infections contribute to stalk and bud damage, including rot and failure to bloom. Before planting yucca, be aware of its need for light soil and sunshine, and site accordingly. A sunny, dry location will prevent bud rot.
  
  

Propagation

• When conditions are moist, yucca buds are prone to rot, but black aphids also prefer moist environments. The insects colonize yucca flower stalks when conditions are warm, moist and favorable. Black aphids destroy flower buds. Not all insects are damaging, however. The pronuba moth is one of the few natural ways in which yucca flowers are pollinated. In areas where the moth is not present, gardeners must hand-pollinate flowers to encourage seeding. Because of this difficulty, most yucca plants are propagated through division or cuttings. Even if your yucca's flower buds are rotting, this will not stop your yucca from reproducing. If damage is severe, then take cuttings from healthy foliage and reproduce your yucca plant.
  
  

Bud Maintenance

• Even if your yucca plant is safe from fungus and black aphids, you may find that your flower stalks still fail to produce blooms. Should this be the case, ensure that you have pruned back the old flower stalk after the current season's yucca flowers have faded. This encourages new growth and flowering for the upcoming bloom season.
  
  

Cultivars

• Yucca plants are highly architectural and are utilized for dramatic effect. Weak spine yucca are used to line walkways, while sharp pointed varieties provide strong backdrops to lower-lying floral beds. Yucca flowers and buds are not always essential to the overall landscape design. Many cultivars feature foliage with a high degree of visual interest. Adam's Needle, a densely spiked, narrow-leaved yucca, features cultivars like Color Guard and Golden Sword that exhibit green leaves with cream-colored or yellow stripes. Yucca gloriosa var. Variegata has blue-green leaves edged with deep yellow tones. When maintaining your plant, keep in mind that caring for the foliage will also result in healthy buds.