Plan for success with planting calendar for vegetable gardens
“How do we get there —
there where blossoms bloom in May,
the fruit waiting in silence?”
– James McGrath, “Mixed Greens: Poems From the Winter Garden,” 2019
After many years of trial and error growing vegetables in raised beds, I can say with confidence the best way to “get there — where blossoms bloom in May” (and throughout the growing season) — is by planning ahead with a planting calendar.
Begin by considering: 1) the vegetables you like to eat, 2) the growing conditions in your garden, 3) the size of your growing space and 4) the time and effort you want to spend in your garden.
Based on records of local weather patterns over the past five years (reported by Weather Underground from the Rogue Valley International-Medford Airport), I can predict with reasonable assurance the last spring frost will take place in my garden by April 18, and the first fall frost by Oct. 23 (dates will vary by a week or two depending on elevation and available sunlight).
Those dates provide me with 196 days for growing vegetables, not including overwintering vegetables or growing indoors or in cold frames during the fall and winter.
Although global warming has lengthened the growing season in the Rogue Valley, it also presents extra challenges for gardeners. Erratic temperatures, particularly in spring and fall, are liable to freeze or burn up plants if gardeners are caught off guard. It is essential to keep track of high and low temperatures and have a protective cover handy.
Summer temperatures have increased (in 2022, there were 42 days with temperatures above 95 degrees during June, July, August and September, as well as several days in the 90s during October). Such extreme temperatures can cause lower germination rates and blossom/fruit drop for heat-sensitive plants such as tomatoes, beans and squash. Lettuce, spinach and brassicas (cabbage, broccoli, cauliflower) tend to bolt sooner.
On the other hand, warmer fall temperatures last year enabled me to continue harvesting tomatoes, beans and peppers until November.
In addition to extended heat waves, wildfire smoke in the valley makes gardening outdoors unhealthy and unpleasant during July and August. This presents challenges for summertime garden maintenance and harvesting and also for starting fall crops.
Then again, having warmer high temperatures during the winter makes working outdoors more pleasant. Gardeners can successfully grow vegetables in cold frames or row tunnels, as long as they don’t forget to uncover them on warmer days and keep them covered on cold nights.
In recent years, our area also has experienced decreases in rainfall and snowfall during fall, winter and spring (in 2022, Medford’s accumulated precipitation was 14.41 inches, which was about 4 inches below normal). This means gardeners must irrigate more, particularly in summer when water supplies are at their lowest. Capturing and storing rainwater during the wet season has become increasingly beneficial.
With these challenges and advantages of the Rogue Valley gardening seasons in mind, it’s helpful to plan your garden by grouping the plants you want to grow into families with similar growing needs.
The vegetables I want to grow this year fall into 10 plant families:
Amaranthaceae (amaranth) family: Swiss chard, beets, spinach (cool weather crops, 45-90 days to maturity)
Amaryllidaceae (allium) family: onions, garlic, shallots, chives (cool weather crops, 60-120 days to maturity)
Asteraceae (aster/daisy) family: lettuce/greens (cool to warm weather crops, 30-45 days to maturity)
Brassicaceae (mustard) family: kale, cabbage, broccoli, cauliflower, Brussels sprouts, radish (cool weather crops, 60-90 days to maturity)
Cucurbitaceae (cucumber) family: cucumbers (also squash and melons) (warm weather crops, 60-90 days to maturity)
Ericaceae (heath) family: blueberries (warm weather crop, 60-90 days to maturity after blossoming)
Fabaceae (legume) family: peas, beans (cool, warm weather crops, 60-75 days to maturity)
Lamiaceae (mint) family: basil, oregano, rosemary, sage, mint (warm weather crops, 45-75 days to maturity )
Rosaceae (rose) family: strawberries (warm weather crops, 30-45 days after blossoming to maturity)
Solanaceae (nightshade) family: tomatoes, peppers, eggplant, tomatillos (also potatoes) (warm weather crops, 60-90 days to maturity)
Based on these maturity days and April 18 as the date of the last spring frost, here is my 2023 planting calendar for my 250-square-foot vegetable garden. By practicing intensive planting, I’m hoping to grow about 30 different kinds of vegetables and herbs, plus annual companion flowers (nasturtiums, alyssum and calendula).
Seed outdoors: peas
Seed outdoors: peas, carrots, radishes, lettuce, bulb onions, kale, spinach
Seed indoors: kale, cabbage, broccoli
Transplant starts: herbs, strawberries
Seed outdoors: peas, carrots, radishes, lettuce, spinach, chives, cilantro
Seed indoors: tomatoes, peppers, eggplant, Swiss chard, companion flowers
Transplant starts: kale, cabbage, broccoli
Seed outdoors: radishes, lettuce, cilantro, chives, beets, carrots
Seed indoors: basil, cucumber, tomatillo
Transplant starts: tomatoes, peppers, eggplant, Swiss chard, blueberry bushes, companion flowers
Seed outdoors: pole beans, beets, lettuce
Transplant starts: basil, cucumber, tomatillo
Seed outdoors: pole beans
Seed indoors: broccoli, cauliflower, cabbage, Brussels sprouts
Seed indoors: lettuce, kale
Transplant starts: broccoli, cauliflower, cabbage, Brussels sprouts
Seed outdoors: onions, peas, turnips, Swiss chard
Transplant starts: lettuce, kale
Seed outdoors: garlic, shallots, cover crops
Seed in cold frame: lettuce/greens
Assess vegetable production and plan for next year
My next step is to transfer this information to a large monthly calendar and organize my seeds for each month’s planting. Next week, I’ll share my plan for planting the vegetable beds. Stay tuned!
Rhonda Nowak is a Rogue Valley gardener, teacher and writer. Email her at Rnowak39@gmail.com.