Not Enough Sunlight

• Inadequate sunlight is one of the most common reasons for failure of redbud trees to produce their characteristic pink blooms. While redbuds are capable of growing in partial sun and light shade locations, they flower most profusely when grown in full sun. Look for a planting site that gets bright, direct sunlight for six or more hours per day to encourage your redbud to set and open healthy blossoms. In especially warm climates, redbuds appreciate sites that provide them with a bit of light, filtered shade during the hottest parts of the day.
  
  

Not Enough Water

• Redbud trees perform best and bloom vigorously in moist, well-drained soil, according to the Clemson University Cooperative Extension Service. Without adequate water, redbuds may hold back their blossoms in order to conserve moisture for their root systems. For best results, water your redbud tree weekly during the spring and summer in the absence of rain. Provide redbud trees with up to 1 inch of water each time you irrigate; keep the soil evenly moistened, but never allow it to become soggy or waterlogged.
  
  

Incorrect Fertilization

• Feeding redbud trees with too much or the wrong kind of fertilizer stimulates them to produce an abundance of foliage, but reduces flowering. However, a carefully timed application of the right type of fertilizer gives your redbud the nutrients it needs to blossom prolifically. Fertilize redbud trees with an application of a high-phosphorus fertilizer in the very early spring, before they present new growth. Apply the fertilizer according to package instructions to avoid damaging your redbud.
  
  

Improper Pruning

• Though many gardeners are accustomed to pruning the trees in their home landscape in the early spring, pruning redbuds in the spring removes their buds and prevents them from flowering. According to the USDA Forest Service, early spring flowering trees such as redbuds should be pruned only after they've finished blooming. Use sharpened and sterilized pruning shears and loppers to remove diseased, damaged, dead or crossing branches from your redbud tree.