Purple Leaf Plum Maintenance

Water

• Although the purple leaf plum will tolerate some drought, it produces more uniform growth and fights off disease and insect pests more readily with consistent moisture. Water a newly planted tree when the top 1 to 2 inches of soil become dry, applying at least 1 inch of water each time. An established plum, 2 to 3 years old or older, requires less frequent watering as its deeper roots draw from water from deep in the soil. As a general rule, water established trees when less than 1 inch of rain falls over a period of seven days, or twice per week when temperatures reach 85 degrees Fahrenheit or higher. Apply 2 to 3 inches of water at each watering to moisten the soil to a depth of 18 to 36 inches.

Fertilizer

• Much like other deciduous trees, the purple leaf plum produces an abundance of new growth in spring, once it breaks from dormancy. During this period of active growth, the plant requires a steady supply of nutrients and water. To provide these nutrients, fertilize the plum each spring, just before its buds begin to swell. Apply 12 1/2 pounds of 24-6-12 slow-release fertilizer to supply the plum with 3 pounds of actual nitrogen per 1,000 square feet, the amount of fertilizer suggested by The Ohio State University for woody plants. Spread the granules in a 12-inch-wide band just underneath the perimeter of the plum's canopy. Mix the fertilizer into the top 3 inches of soil, then water the area thoroughly.

Pruning

• To avoid removing flower buds and reduce flowering, prune the purple leaf plum immediately after the plum finishes blooming. Only use sterile, sharp tools to avoid spreading plant diseases or injuring the plant. Cut out all broken, cracked, diseased and crossing branches, making each cut 1/4 inch above an outward-facing bud, side branch or branch bark collar, the swollen ring of bark surrounding the limb where it joins with the trunk. Thin the remaining branches by no more than one-quarter to one-third. Pruning shears work best on branches with diameters of 1/4 inch or less and loppers cut easily through branch diameters of 1/4 to 1 1/2 inches. Cut through larger branches with a pruning saw.

Miscellaneous Maintenance

• Keep the area surrounding and underneath the purple leaf plum tree's canopy free from weeds to eliminate competition for water and nutrients. Spread a 2- to 3-inch-deep layer of mulch around the plum to prevent weed growth and reduce soil moisture evaporation. Pull the mulch back 4 inches from the plum's trunk to ensure proper air circulation and prevent the plant's bark from rotting. Replenish or replace the mulch each year in the spring after fertilizing the plant.