The flowering almond (Prunus glandulosa) is a favorite shrub with ½-inch pink flowers that bloom profusely in spring before its leaves appear. It thrives in partial shade to full sun. This plant looks attractive either as a single plant or when you grow several of them and keep them pruned to form a hedge along garden borders. It can attain a height of 6 feet and tolerates temperatures as low as minus 40 degrees Fahrenheit. This shrub was introduced to the U.S. from its native China in 1835.
Test the soil pH in early spring before you plant your almond: it should be between 5.5 and 7.5. If you need to increase pH, add hydrated lime to your soil; if you need to lower it, add an acid-based fertilizer.
Dig a hole larger than the root ball of your young almond, and then mix in 1 to 2 gallon bucketfuls of compost. Place your plant in the hole, and fill in with the soil you dug out. If you build a small berm surrounding the planting hole, you can flood the tree when you water it, and the water will not run off.
Water your flowering almond deeply once each week during the summer by flooding the area where it is planted, and check the soil periodically to make certain it does not stay soggy.
Fertilize young flowering almonds when you plant them with a high phosphate fertilizer (for example, 10-20-10), and reapply this same fertilizer once each month until fall. If you want to increase flower production, fertilize with a low-nitrogen fertilizer (0-10-10) when the plant begins to show new growth in the spring. Fertilize older almonds only once each year.
Prune your flowering almond in winter, during its dormant season. First look for and cut off any damaged or diseased branches, and then cut all other branches down to about half their length. This will promote bushiness and improve blooming the following summer.
Watch for aphids and caterpillars, and treat them as soon as you notice them. Spray aphids with insecticidal soap and caterpillars with Bt (Bacillus thuringiensis).
Control fungal diseases, such as powdery mildew and leaf spot, by keeping this shrub well-pruned and by raking up fallen leaves around its base. Do not overhead water this plant. You can apply a commercial fungicide if the condition does not improve with cultural controls.