□ □
[□] □
□* □
Apple and pear trees require patience , knowledge and skill to grow well . Within two weeks , a rust-colored pustule containing spores develops in the center of each spot on the lower leaf surface . Disease Cycle : The white fuzzy growth on the leaf surface contains thousands of fungal spores . Such conditions allow water to be absorbed by the plant but lost only slowly by means of normal transpiration through the leaf surface . Astilbe , coneflowers and rudbeckia all have attractive flowers and form that create visual beauty in the winter . Because currants and gooseberries do not perform well under dry or waterlogged conditions , most soils will benefit from the addition of organic material such as shredded peat or compost before planting . Poor air movement increases danger of spring frost injury to blossoms and favors disease development .