In January and February, Western Oregon is often one of the mildest locations in the country with daytime high temperatures in the 50’s while most of the country is frozen solid. Now flash forward to the end of April and our daytime high temperatures are still in the 50’s, while the rest of the country has unthawed and zooming into the 70’s or 80’s.
This regional weather condition is caused by the moderating effect of the Pacific Ocean that keeps us mild in winter and mild in spring. Understanding this climatic feature should stop you from planting summer annuals too early. Learning other nuances of temperature and climate in our coastal region can make you a better gardener by putting you in touch with our seasonal norms.
Western Oregon is an excellent place to grow winter vegetables that tolerate cool temperatures with some short periods of freezing weather. These plants include garlic, onions, peas, spinach, broccoli, cauliflower, cabbage, lettuce, kale, collards and leeks.
If your garden is an in-ground plot and you start plants from seed, you will need to plant in early fall, when the soil is still warm, to get plants up and established before the cold of winter. Once established, plants grow slowly during winter and become productive as temperatures warm in spring.
If you have raised beds you, can transplant starts into the beds in late fall and the plants will mature by spring. To be very successful in winter gardening, put up plastic hoop covers over your garden or raised beds to keep the rain off. This will allow the soil to warm by 5-10 degrees, promoting additional growth.
Climatically the most limiting factor of winter gardening in our area is excess rainfall, not cold temperatures. This winter has had a number of weeks without rain, allowing soils to warm a few extra degrees.
In our maritime climate soil is normally very slow to warm up. And soil temperature is the real key to when you should plant your warm season garden. With excess rainfall in spring and cool temperatures, saturated soil does not warm quickly. To garden more effectively in spring, use raised beds. Raised beds have better drainage than in-ground gardens and they dry out faster and warm up sooner.
If you have an in-ground garden, be patient until soil temperature hits 60 degrees before planting warm season vegetable seeds or transplants. Given our current rainfall pattern with plenty of dry weeks I would expect to see a nice, normal spring. That would mean being patient and waiting for our normal late April to plant your garden. This will save you the extra cost and effort of planting several times.
Once the rain stops and soil warms, your plants will grow better if they have uninterrupted good conditions. Your soil will be better off too if you do not try to cultivate it when soil is wet.
When getting ready for your spring planting season, be advised that the Master Gardeners and I will be having a Spring Into Gardening educational program at the Phoenix School from 9 a.m. to 4 p.m. Feb. 29.
You may register online at www.bit.ly/2uOFT12 or come by the OSU Extension office, 1134 SE Douglas Ave., Roseburg, during business hours until Feb. 20.
This program will have a wide variety of topics to choose from during four 1.5 hour sessions. The cost of the day long program is $25. Bring your gardening questions along. We would love to help you.