Types of Garden Enemies
In wet years it blights dogwood, infected anthers and bracts rotting onto young leaves. It affects leaves, flowers, and corms of gladiolus grown in Florida and humid sections of the Northwest. The gray mold kills stems of eupatorium, causes a basal rot of pansies (especially if they are held too long in the box before being planted in your garden); it rots lettuce and lima beans. If raspberries and strawberries are picked in damp weather, half the box may be covered with mold by the time it gets to your kitchen.

Control. Cut fading flowers into a paper bag as you walk around the garden; dig up and destroy blighted pansies and lettuce; ignore the dogwood blight; spray gladiolus with Dithane Z-78 or Parzate; keep green- house plants widely spaced with good ventilation and avoid overhead watering.

LILY BOTRYTIS BLIGHT (Botrytis elliptica),
general on lilies but most serious on Madonna lilies. If blight strikes early the entire growth can be killed, but more often the disease starts with oval, reddish or orange brown leaf spots (Figure 13C) which later grow together to infect the whole leaf. In cool, moist weather blight starts on the lowest leaves and works progressively up the stem, until most of the foliage is blackened and hanging limp. Buds rot or open to distorted flowers with irregular brown specks. The fungus winters either in very small black sclerotia formed on fallen petals, dead stems, or leaves or as mycelium in the basal rosettes of Madonna lilies.

Control. Avoid too dense planting; avoid shady and low spots with little air circulation; cut out blighted stalks before sclerotia can be formed. Spray with bordeaux mixture or a fixed copper at 10- to 14-day intervals from the time lilies are a foot high to flowering.

PEONY BOTRYTIS BLIGHT (Botrytis paeoniae),
present wherever peonies are grown. In a rainy spring young shoots rot off at the base as they come through the ground or shortly thereafter, especially if they have to emerge through a leaf mulch or manure. Small buds turn black and never develop, half-open buds blast, or full-blown flowers turn brown, with a short, thick, velvety gray mold covering affected parts in moist weather. Leaves have brown spots when fading flowers rot onto them. Small, flat, black sclerotia are formed closely appressed to the stalks, usually near the base.

Control. Cut all stalks in October at ground level; do not leave even an inch of stubble. You can mark the spot, so you don't disturb peonies in bulb planting or other operations, by three sticks at the circumference of each planting. Burn all tops; never use them for a winter mulch; avoid mulches, except possibly salt hay the first season after planting.




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