August 12, 1994

Adirondack Crabapple


Malus 'Adirondack', introduced by the National Arboretum in Washington, DC, is a small tree with a pronounced vertical branch habit. A typical specimen might grow 12 feet tall and 6 feet wide, taking on an upright, egg-shaped outline.

Artemisia


Plants grown for their foliage effect add a special touch to the flower garden. This is especially true during the transition between summer and fall when flower color in the garden is lacking. Gray foliage intensifies the color of nearby flowers and other foliage and ties together almost every color combination imaginable.

Summer Tree Maintenance... Watering


Water plays many key roles in a tree's life. When water is in short supply, trees cannot function normally and will eventually die if the deficit is not corrected.

Iris Leaf Spot


Leaf spot is a common disease of iris, especially rhizomatous species. It is caused by the fungus Didymellina macrospora. The first evidence of the disease is the appearance of small yellow-brown spots on leaves that are surrounded by a water-soaked border. The spots enlarge, turn brown and dry. The older spots are surrounded by a dark reddish-brown border. Large dead areas may occur when spots enlarge and merge and leaves may be killed prematurely.

Harvesting and Sorting Potatoes


Potatoes grown for winter use should be harvested after the vines have died and the crop is mature. To check maturity, dig up one or two hills of potatoes. If the skins on the tubers are thin and rub off easily, the crop is not fully mature and will not store well. Wait a few more days before harvesting. The skins on mature potatoes remain firmly attached to the tubers. When harvesting potatoes, avoid bruising, skinning, or cutting the tubers. Damaged potatoes should be used as soon as possible.