Plumcot Trees

Tree Characteristics

• Standard size plumcot trees grow 10 to 20 feet tall with a greater spread, although dwarf varieties generally reach no more than 10 feet tall. In spring, plumcot trees clothe themselves in white or pale pink blossoms. Derived from a cross between a Japanese plum and an apricot, plumcots require cross-pollination to set fruit. Almost any Japanese plum tree, such as "Santa Rosa," can pollinate plumcots. "The New Sunset Western Garden Book" recommends planting low-chill-requirement plumcot "Flavorosa" as a pollinator, or low-chill apricots "Floragold" or "Gold Kist." Fruit ripens in late spring or early summer.

Culture

• Plumcot trees grow best in full sun in well-drained, loamy soil with a pH range of 6.0 to 7.0. When planted, the bud-graft-line of grafted trees should remain above ground. Fertilize your plumcot tree one month after planting and then every spring before leaves emerge. Calculate the amount of fertilizer to use by measuring your tree trunk diameter 1 foot from the ground. Apply 1/8 pound of nitrogen per inch of tree-trunk diameter. Calculate the amount of nitrogen in a particular fertilizer blend by dividing the first number, which represents nitrogen, into 100. For example, for a fertilizer blend with analysis 5-10-10, divide 5 into 100, which equals 20. Twenty is the number of pounds of the fertilizer blend required to obtain 1 pound of nitrogen. To apply 1/4 pound of nitrogen to a 2-inch diameter tree, divide 20 by 4, which equals 5 pounds or 10 cups. Irrigate thoroughly with a soaker hose to ensure 1 inch of water every 10 days the first year. After your plumcot is established it is able to withstand mild drought. Plumcots are subject to brown rot, gummosis and peach tree borers. Good cultural practices diminishes the likelihood of these problems.

Prune

• Naturally wide-spreading branches reduce the need for pruning plumcot trees. During the dormant season, remove dead, diseased or weak branches. Summer prune to retard plant growth. Make thinning cuts to remove vigorous new shoots, cutting back to side shoots. Removal of new growth reduces the tree's food supply, limiting growth. When your plumcot puts on a heavy crop, thin fruit to 8 or 9 inches apart to prevent the tree from producing a light crop in the subsequent year.

Chill Hours

• Chill hours is a term referring to the number of hours when temperatures are 45 degrees or below during the months of November through February, the dormant season. Plumcots are generally a low-chill-requirement fruit tree, needing between 400 and 800 chill hours, depending upon variety. "Flavorella" requires 400 to 500 chill hours to set fruit,