In Ashland, Oregon the last frost date is approximately May 15th.

Sow seeds in your greenhouse, or indoors,  for transplanting  after May 15th.
Basil, Cabbage, Peppers, Summer Squash, Winter Squash, Pumpkin, Tomato, etc.
Flowers;  Sunflowers, Cosmos, Marigolds , Zinnia, etc.

If the soil is not too wet, you can sow the following vegetables seeds directly into the garden. Once seedlings emerge protect them from spring frost.  Lettuces, Cauliflower, Spinach, Chinese Cabbage, Broccoli, Peas, Chard, Carrots, Turnips, Parsnips, Leeks, Kohlrabi, Beets, Radishes.

You can plant onion sets up until 4/15. And, you can still plant raspberries and strawberries plants.
Fertile flowerbeds, shrubs, trees and grass.
Start baiting for slugs, snails and earwigs.
Watch out for spittle bugs and aphids on your existing strawberry plants.
Watch out for aphids on all plants in the landscape.

• Home remedy for Aphid Control: Mix a teaspoon of vegetable oil, a teaspoon of dishwashing liquid and a cup of water. Or, mix three tablespoons of liquid soap and a gallon of water. Spray to wet the entire plant thoroughly, particularly the undersides of leaves, because aphids must come into contact with the soap solution to be affected. After a few hours, wash off the oil and soap with a garden hose to protect sensitive plants. Repeat the application every few days as necessary.
• Control spittle bugs by blasting spittle bug foam off plants with water. Repeat as necessary.

Pruning shrubs & trees should be completed by now!