Garden Calendar

This garden calendar is specifically timed to fit the low elevation areas of Washington and Oregon west of the Cascades. Typical average last frost dates vary from early to late April. Typical first fall frost date is early to late October. It can be adapted to higher elevations and different frost dates by delaying early spring activities and doing fall activities earlier. Allen is available for free email or telephone consultation on garden and landscape problems and questions. allen@naturalpruningnw.com, 360-606-5437

January is an ideal time to prune deciduous trees and shrubs except spring flowering shrubs. It is also an ideal time to plant new trees and to move trees and shrubs from one location to another in the landscape. This is a great time to make garden plans for remodeling or improving the landscape. Landscape professionals are not as busy now and their services are more readily available. Some vegetable and flower seeds can be started inside for later outside planting. (See Starting Seeds Inside)

Dormant oil can be applied to fruit trees and shade trees to kill overwintering insect pupae and eggs.

February is the month of awakening for many plants in the Pacific Northwest. Buds begin to swell on trees and shrubs and new sprouts appear on many bulbs and perennial flowers. Flowering shrubs and trees such as Forsythia and Flowering Plum often begin to open by the end of the month.

This is ideal planting time for deciduous trees and shrubs such as roses, fruit and shade trees. Bare root or root wrapped plants should be planted before leaf growth starts.

Hardy flowers such as primrose and pansy can be planted. Summer flowering bulbs (dahlia, tuberous begonia, gladiolus, lily, calla lily, ranunculus, anemone) become available in nurseries and garden stores. All except dahlia and begonia can be planted in February or March. Wait until April to plant dahlia and begonia bulbs.

February is also an ideal time to prune deciduous trees and shrubs except spring flowering shrubs. Mid February is considered the ideal time to prune roses and summer flowering hydrangeas.

This is spring cleanup time in the garden when last year’s dead perennial growth is removed and dead leaves are pruned off of ferns and ornamental grasses.

February is an ideal time to remove thatch and aerate lawns. Consider applying humates to reduce lawn thatch instead of using power tools. Humates also stimulate micro-organisms and fertilize lawns and other plants.

Dormant oil can be applied to fruit trees and shade trees to kill overwintering insect pupae and eggs.

March says “Spring is Here” in the Pacific Northwest. New growth begins on many plants and some of our premier flowering trees and some fruit trees begin to bloom. Asparagus and rhubarb may be ready to harvest by the end of the month.

This is an ideal time to plant trees, shrubs, perennial flowers, most summer flowering bulbs, and lawns. Hardy fruits such as raspberry, strawberry and blueberry may be planted outside. Vegetables such as pea, broccoli, cabbage, lettuce, spinach, radish, carrot, onion and asparagus can be seeded or transplanted outside. Hardier annual flowers such as snapdragon, petunia and alyssum can be planted outside by the middle of March. Wait until April or May to plant tender annual flowers such as impatiens, begonias, marigolds and zinnias and tender vegetables such as tomatoes, peppers, cucumbers, squash and melons.

March is a good month to prune most plants except spring flowering shrubs.

Trees, shrubs, lawns and perennial flowers can be fertilized this month. Lawns which were fertilized in October or November can wait until April or May for fertilizer.

Weed control and some pest control begin this month. Clear out those old winter weeds and newly sprouting spring weeds. Lawn weeds can be controlled with Weed and Feed products or selective lawn weed killers. Moss can be controlled with iron compounds in Moss Out and similar products.

April is the middle of spring planting season in the Pacific Northwest. Everything but tender annual flowers and vegetables can be planted by early April. Tender annual flowers and vegetables can be planted in lower elevations by the end of the month. See “hardy flowers and vegetables” in the how to guide.

Fertilize plants when they are planted. Established plants should be fertilized in March or April. Most plants except spring flowering shrubs can be pruned in April. Lawns not fertilized in March can be fertilized in April or May (depending upon fall fertilizer application). See “Spring Lawn Care” in How to Guide.

Roses should have their first application of fungicide to protect against black spot, mildew and rust leaf diseases. Flowering cherries, peaches, photinia, and dogwood are also plagued by their own leaf spot diseases. It is important to clean up and dispose of old leaves of these plants because they are a source of spores for reinfection. The ideal application time is just as new leaves are developing. Peaches and nectarines must be sprayed when new leaves are just emerging to prevent peach leaf curl. See “leaf diseases” in the how to guide.

Broad leaf lawn weeds can be controlled by selective liquid or granular weed killers. Pre-emergent weed preventers such as Casoron and Preen can be applied before there is much new weed growth. Moss can be controlled with iron compounds in Moss Out and similar products.