OSU Gardening Calendar

March

Planning

Plan the vegetable garden carefully for spring, summer, and fall vegetables that can be eaten fresh or preserved. If you lack in-ground gardening space, plan an outdoor container garden.
Use a soil thermometer to help you know when to plant vegetables. Some cool season crops (onions, kale, lettuce, and spinach) can be planted when the soil is consistently at or above 40°F.

Maintenance and Clean Up

Lawn mowing: Set blade at 0.75 to 1 inch for bentgrass lawns; 1.5 to 2.5 inches for bluegrasses, fine fescues, and ryegrasses.
Compost grass clippings and yard waste, except for clippings from lawns where weed-and-feed products or herbicides (weed killers) have been used.
Spread compost over garden and landscape areas.
Prune gooseberries and currants; fertilize with manure or a complete fertilizer.
Fertilize evergreen shrubs and trees, only if needed. If established and healthy, their nutrient needs should be minimal.
If needed, fertilize rhododendrons, camellias, azaleas with acid-type fertilizer. If established and healthy, their nutrient needs should be minimal.
Western Oregon: Prune spring-flowering shrubs after blossoms fade.
Western Oregon: Fertilize caneberries (broadcast or band a complete fertilizer or manure).

Planting/Propagation

Divide hosta, daylilies, and mums.
Use stored scion wood to graft fruit and ornamental trees.
Plant insectary plants (e.g. Alyssum, Phacelia, coriander, candytuft, sunflower, yarrow, and dill) to attract beneficial insects to the garden. See PNW550 (Encouraging Beneficial Insects in Your Garden) for more information.
Central Oregon: Sow chard seeds outdoors. Plant seed flats of cole crops (cabbage, cauliflower, broccoli, and Brussels sprouts) indoors or in a greenhouse.
Western Oregon: If soil is dry enough, prepare vegetable garden and plant early cool-season crops (carrots, beets, broccoli, leeks, parsley, chives, rhubarb, peas, radish). Plant onions outdoors as soon as the soil is dry enough to work.
Western Oregon: Plant berry crops (strawberries, raspberries, blueberries, blackberries, currants, gooseberries, and other berry-producing crop plants). See OSU Extension publications for varieties.

Pest Monitoring and Management

Monitor landscape plants for problems. Don't treat unless a problem is identified.
Spray trees and shrubs for webworms and leafrollers, if present.
Protect new plant growth from slugs. Least toxic management options include barriers and traps. Baits are also available for slug control; iron phosphate baits are safe to use around pets. Read and follow all label directions prior to using baits or any other chemical control.
Learn to identify the predatory insects that can help keep aphids and other pests under control.
Spray to control leaf and twig fungus diseases in dogwood, sycamore, hawthorn, and willow trees.
Prune ornamentals for air circulation and to help prevent fungus diseases.
Western Oregon: Monitor for European crane fly and treat lawns if damage has been verified.
Western Oregon: Start rose blackspot control tactics at budbreak. Control rose diseases such as black spot. Remove infected leaves. Spray as necessary with registered fungicide.

Houseplants and Indoor Gardening

Trim or shear heather when bloom period is finished.
Start tuberous begonias indoors.
Western Oregon: Take geraniums, begonias, and fuchsias from storage. Water and fertilize. Cut back if necessary. Move outdoors next month.

Download a PDF of the March Calendar for easy printing.

Updated September 10, 2009.

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