If ever there was a month for planting, October is it! Fall is solidly underway this month, bringing perfect planting weather to our Pacific Northwest Gardens. Warm days and cool nights trigger plants to begin shutting down growth on top and directing energy into root development. Plus, seasonal rains arrive to help new plantings get established. That's why this month is primarily dedicated to adding new trees, shrubs, and bulbs to the landscape. But in between plantings, don't forget to take a step back to enjoy the sights of autumn, from the mounded mums on our doorsteps to the towering Jerusalem artichokes in our Kitchen Gardens.
In the Garden
If you are looking to add some seasonal fall color to your outdoor spaces, in addition to the ever-popular ground cover plumbago (Ceratostigma plumbaginoides), why not grab some mums, pansies, ornamental kales, and more for your containers and beds? Now is also great time to plant hardy perennials for color throughout the autumn and winter seasons — and don't forget all-star fall grasses like bluestem and switchgrasses. These beauties can knit together a planting like nothing else and look absolutely stunning this time of year.
October is also the perfect time for planting trees, vines, and shrubs like the beautiful sourwood tree (Oxydendrum arboreum) pictured here, which starts to show fall color in our display gardens towards the end of the month. The moist autumn soil makes for easy digging — plus, it’s fantastic for root systems. Planting now ensures your trees and shrubs are able to develop successful, deep root systems over the colder winter months before spending time and nutrients building foliage above ground. Be sure to water your trees in immediately after planting, and continue regularly watering until daytime temps drop below 45°F. Hemlock and fir mulch can also protect new trees by helping the soil retain moisture and nutrients.
We often have guests ask us which trees and shrubs they should plant for vibrant fall color. Our expert, Darla, suggests the following:
It may be fall, but don't forget to look towards the spring when you're planting, as well! In addition to the many perennials that can be planted this time of year, bulbs are out at the Patio! We have curated a selection of bulbs that perform well in the PNW climate so that they will multiply year after year, providing you with blooms each spring.
Plants with Purpose
You may remember that we celebrated the 52st anniversary of Earth Day back in April of this year. Cornell Farm remains committed to sustainable and ecologically friendly gardening practices and focused on making this planet better. Since planting season is upon us, we would also like to encourage our patrons to support these initiatives by choosing native and drought-tolerant plants for their gardens. Instead of planting grass seed for your yard this fall, consider planting some native grasses and wildflowers instead. Not only will you be lowering your water use, but you will also be supporting your local ecosystem and wildlife!
While you have likely already planted your edible winter crops (if not, don't panic!), you will need to plan to keep these plants protected from frost and freeze as we near the end of October, either by constructing cloches or using Harvest Guard® protective fabric. Pay attention to overnight temps (under 34-35°F), and be sure to have these protectors ready before the first frost!
As your summer plants, perennials, and veggies begin to die, pull out and compost annuals and other brown foliage. Unless you are leaving seed heads for winter bird forage or stems for overwintering insect life, it is also a good idea to cut back any lanky, out-of-bloom perennials at this time. Once beds are cleaned up, sow winter cover crops or top off with compost to prevent weeds and enrich next season's soil. If you plan to collect seeds, bring them inside and store them in a cool, dark, dry place. Fallen leaves — particularly maple, alder, and oak — can provide excellent compost material, as well as habitat for beneficial insects and soil microbes. (We have some excellent expandable rakes in stock, which are real space-savers for gardeners short on tool storage space.) If you are able, you should leave a little decomposing plant material in your garden to help promote a healthy ecosystem in areas where you don’t plan to sow cover crops.
While cleaning up your garden, you may find now is a good time to do light pruning on roses to remove crossing branches. As always, be sure to use clean, sharp tools!
On that note, once you are satisfied with your winter garden, be sure to spend some time cleaning and storing your gardening tools and hoses. Drain and clean these items, then place them in a dry spot so that they are ready for next season.
After you have cleared space, planting cover crops will cultivate better soil for spring, as well as help provide habitat and nutrients for a healthy soil ecosystem. Sow hardy crops like fava beans that favor colder soil temperatures, and be sure to keep these areas covered until they germinate.
Early October is also the perfect time to plant onions and garlic! We have a wide variety to choose from in-store. Planting after the fall equinox gives these easy growers a jump start so that they will be among the first sprouts in spring. Aside from the obvious delicious benefits of planting onions and garlic, they also have the added benefit of deterring deer from helping themselves to your veggie garden.
Some varieties of hardy greens like spinach and kale can still be planted in a warm spot in early October. Kale, in particular, is resilient in our cold temperatures, providing greens through the winter months. It is still a good idea to cover any hardy greens with a cloche to protect them from the colder evenings.
Transition citrus plants to porch cover when night temperatures dip to 38°F. If temperatures are projected to be 32°F or lower, move your citrus plants to space that will be between 40 and 60°F until outside temperatures are 38°F or above — for as short a time as possible. Citrus will perform best when temperature and light transitions are kept to a minimum. You can help your plants adjust to the change from outdoors to in by moving them next to a warm wall under cover for several days, then indoors to a cool-but-sunny room. (The same is true in reverse for moving them back outdoors.) After all, citrus are outdoor plants and do best with plenty of sunshine and air movement, as found in natural conditions.