April Gardening Calendar
Oregon State University Extension Service encourages sustainable gardening practices. Always identify and monitor problems before acting. First consider cultural controls; then physical, biological, and chemical controls (which include insecticidal soaps, horticultural oils, botanical insecticides, organic and synthetic pesticides). Always consider the least toxic approach first.
All recommendations in this calendar are not necessarily applicable to all areas of Oregon. For more information, contact your local office of the OSU Extension Service.
* Early April: fertilize lawn, let spring rains carry the fertilizer into the soil.
* If lawns are becoming thin and sickly, consider overseeding with a mixture of perennial ryegrass and fine fescue.
* Protect dogwood trees, as they begin growth, against anthracnose diseases. Apply a copper fungicide or Daconil. Rake and destroy fallen leaves spring through fall.
* Help youngsters start a garden this year with carrots, chard, lettuce, onions, and peas.
* Bait for slugs; iron phosphate baits are available that are safe for use around pets. Clean up hiding places for slugs, sowbugs, and millipedes.
* Allow foliage of spring-flowering bulbs to brown and die down before removing.
* Prune and shape or thin spring-blooming shrubs and trees after blossoms fade.
* Control rose diseases such as black spot and powdery mildew. Remove infected leaves. Spray as necessary with registered fungicide. Prune ornamentals for air circulation and to help prevent fungus diseases.
* Prepare garden soil for spring planting. Incorporate generous amounts of organic materials and other amendments as needs are shown by soil analysis.
* Plant early broccoli varieties for western Oregon: Green Valiant, Premium Crop, Packman, or Rosalind.
* Use floating row covers to keep insects such as beet leaf miners, cabbage maggot adult flies, and carrot rust flies away from susceptible crops.
* Monitor strawberries for spittlebugs and aphids; control if present.
* Cut and remove weeds near the garden to remove sources of plant virus diseases.
* Spray for apple scab, cherry brown rot, and blossom blight. See EC 631, Controlling Diseases and Insects in Home Orchards.
* Apply commercial fertilizers, manure, or compost to cane, bush (gooseberries, currants, and blueberries), and trailing berries.
* Plant gladioli, hardy transplants of alyssum, phlox, and marigolds, if weather and soil conditions permit.
* Prepare raised beds in areas where cold soils and poor drainage are a continuing problem. Add generous amounts of organic materials.
* Place compost or well decomposed manure around perennial vegetable plants.
* Watch for botrytis blight on peonies.
* Check started seeds for damping-off.
* Cover transplants to protect against late spring frosts.
* Plant these vegetables:
Oregon coast: beets, cabbage, carrots, cauliflower, celery, chard, slicing cucumbers, endive, leeks, lettuce, onion sets, peas, potatoes.
Western valleys, Portland, Roseburg, Medford: broccoli, Brussels sprouts, cabbage, carrots, cauliflower, chard, chives, endive, leeks, lettuce, peas, radishes, rhubarb, rutabagas, spinach, turnips.
Central Oregon and higher elevations of eastern Oregon (late April): peas, radishes, lettuce, spinach, turnips.
Columbia and Snake River valleys, Ontario: snap and lima beans, beets, broccoli, Brussels sprouts, cabbage, carrots, cauliflower, chard, chives, sweet corn, slicing and pickling cucumbers, kohlrabi, leeks, lettuce, onion sets, parsnips, peas, potatoes, pumpkins, radishes, rhubarb, rutabagas, summer and winter squash, turnips.
Oregon State University Extension Service encourages sustainable gardening practices. Always identify and monitor problems before acting. First consider cultural controls; then physical, biological, and chemical controls (which include insecticidal soaps, horticultural oils, botanical insecticides, organic and synthetic pesticides). Always consider the least toxic approach first.
All recommendations in this calendar are not necessarily applicable to all areas of Oregon. For more information, contact your local office of the OSU Extension Service.
* Early April: fertilize lawn, let spring rains carry the fertilizer into the soil.
* If lawns are becoming thin and sickly, consider overseeding with a mixture of perennial ryegrass and fine fescue.
* Protect dogwood trees, as they begin growth, against anthracnose diseases. Apply a copper fungicide or Daconil. Rake and destroy fallen leaves spring through fall.
* Help youngsters start a garden this year with carrots, chard, lettuce, onions, and peas.
* Bait for slugs; iron phosphate baits are available that are safe for use around pets. Clean up hiding places for slugs, sowbugs, and millipedes.
* Allow foliage of spring-flowering bulbs to brown and die down before removing.
* Prune and shape or thin spring-blooming shrubs and trees after blossoms fade.
* Control rose diseases such as black spot and powdery mildew. Remove infected leaves. Spray as necessary with registered fungicide. Prune ornamentals for air circulation and to help prevent fungus diseases.
* Prepare garden soil for spring planting. Incorporate generous amounts of organic materials and other amendments as needs are shown by soil analysis.
* Plant early broccoli varieties for western Oregon: Green Valiant, Premium Crop, Packman, or Rosalind.
* Use floating row covers to keep insects such as beet leaf miners, cabbage maggot adult flies, and carrot rust flies away from susceptible crops.
* Monitor strawberries for spittlebugs and aphids; control if present.
* Cut and remove weeds near the garden to remove sources of plant virus diseases.
* Spray for apple scab, cherry brown rot, and blossom blight. See EC 631, Controlling Diseases and Insects in Home Orchards.
* Apply commercial fertilizers, manure, or compost to cane, bush (gooseberries, currants, and blueberries), and trailing berries.
* Plant gladioli, hardy transplants of alyssum, phlox, and marigolds, if weather and soil conditions permit.
* Prepare raised beds in areas where cold soils and poor drainage are a continuing problem. Add generous amounts of organic materials.
* Place compost or well decomposed manure around perennial vegetable plants.
* Watch for botrytis blight on peonies.
* Check started seeds for damping-off.
* Cover transplants to protect against late spring frosts.
* Plant these vegetables:
Oregon coast: beets, cabbage, carrots, cauliflower, celery, chard, slicing cucumbers, endive, leeks, lettuce, onion sets, peas, potatoes.
Western valleys, Portland, Roseburg, Medford: broccoli, Brussels sprouts, cabbage, carrots, cauliflower, chard, chives, endive, leeks, lettuce, peas, radishes, rhubarb, rutabagas, spinach, turnips.
Central Oregon and higher elevations of eastern Oregon (late April): peas, radishes, lettuce, spinach, turnips.
Columbia and Snake River valleys, Ontario: snap and lima beans, beets, broccoli, Brussels sprouts, cabbage, carrots, cauliflower, chard, chives, sweet corn, slicing and pickling cucumbers, kohlrabi, leeks, lettuce, onion sets, parsnips, peas, potatoes, pumpkins, radishes, rhubarb, rutabagas, summer and winter squash, turnips.