Hooray for fall! October is usually easy on people and plants. Although we can have plenty of hot days, the days are shorter and the nights are cooler. We might even get some rain. Fall colors start to appear while some heat-loving plants are still blooming strong.
Planting: In the vegetable garden, plant chard, spinach, turnips, beets, snow peas, carrots, cilantro, lettuce and Asian greens from seed. You can also continue to plant seedlings of greens, broccoli, cauliflower, cabbage and bulb onions. This year I have planted more flowers in the edible garden and I love it! For fall, you can plant snapdragons, calendula, stock, viola and even poppies either as companions or in their own bed. It sure brightens things up, and the beneficial insects seem to also approve.
This is the month to plant most species of trees, shrubs, perennials, vines and ground covers. Wait until spring for citrus, avocado and anything else that is frost sensitive. If you are re-doing your whole yard, October is a great month to do it in. Planting can happen all month but is especially successful if done later in the month, hopefully after the first good storm. Have your irrigation system ready before you plant. Those new transplants will need regular water for at least the first two weeks. Don’t plant too deep; for all plants, leaving an inch or two of the crown above the soil level is best. The planting hole should be as wide as the nursery container, even a little wider if you can do it. Top off with two or three inches of mulch after planting, but make sure that crown is not buried or covered. I don’t personally like adding amendment or fertilizer to the planting hole but if you do, never add fertilizer when planting California native plants like Ceanothus, Flannel bush, Manzanita and bush Lupine, or for succulents and cacti. If you have a large property, consider planting a native oak tree this year. Although you will not see it reach its full mature size, there is something hopeful and resolute in the act of planting an oak tree. The species you plant will depend on your elevation, so do a little research first. Last month I collected acorns from the massive blue oak (Quercus douglasii) in my yard and have stored them in the refrigerator, a treatment called cold stratification. This month I will plant them and soon will have new oak trees to share and to plant in other parts of the property.
Maintaining: Complete your annual yard clean up, especially if you have planting beds or entire yards based on naturalistic styles. Don’t be afraid to cut those spring-blooming shrubs back to a third or half their size. Don’t trim deciduous trees yet; we’ll wait until winter for that. Deadhead roses one final time for a fall bloom. Divide perennials and replant. You can replant iris or wait another month. If you can, grind up the trimmings and use them as mulch for the garden, or add ground-up plant debris to the compost bin.
Deep water your trees a little extra as they enter dormancy unless we get several nicely spaced storms. Adjust automatic systems to reflect cooler temperatures. In the mountains and foothills, wrap your pipes and remove and store faucet timers before the first frost.
Mow warm-season lawns a little shorter and overseed with perennial rye seeds if you want green grass in the winter. For brown patches in lawns, scratch the surface with a rake and spread ¼-inch mulch over the brown patch.
Preemergent herbicide can be applied, except where you plan to grow wildflowers, to help prevent annual bluegrass, mustard, mallow (cheeseweed), clover and purslane. Just like with grass and edibles, we have two main seasons of weeds: warm and cool. October is the month all the cool season weeds start popping up. Be ready!
This is a good month to check your tree stakes in anticipation of winter winds. If the tree can stand up on its own and the root ball seems secure, remove the stakes completely, and let it bend in a breeze; this will help the trunk gain strength. Stakes should never be right up against the trunk. Those stakes are for transporting from the nursery, not long-term. If you need to stake a tree, we have information on our website on how to do it properly: bit.ly/30cnl7K
Go easy on the nitrogen-heavy fertilizer as we go into fall to avoid frost burn of new tender foliage. This is the season, however, to fertilize cool-season lawns and winter-blooming annuals and perennials.
Conserving: Top dress your planting beds and even your lawn with compost. Add another layer of organic mulch to keep your soil healthy. Healthy soil is a vital part of the thriving garden, although it’s easy to take it for granted. Mulch, whether organic or inorganic (rock and decomposed granite) also decreases damage to the soil from rain and reduces both wind and water erosion. You may think about creating a rain garden this year, which can be a way to keep more storm water on your property for use by your plants and the microorganisms in the soil. It can be as simple as a natural low area in the garden. Remove any lawn and weeds. Line it with river rock of varying sizes, with perhaps a boulder or two if you wish. Plant riparian native plants around the borders, such as California goldenrod (Solidago velutina), California fuscia (Epilobium californica), field sedge (Carex pansa) and perhaps a western spice bush (Calycanthus occidentalis).
Although we have to manage many pest insects in the cool of fall, especially in our edible gardens, identify an unknown insect before you kill it or use insecticides. You may be surprised to find you have a wonderful ally.
As always, take some time, especially this year, to enjoy your garden. Allow it to help you as you help it. Plants live on a different time scale than we do, one that can be calming if we start to notice it. One of the best ways to do this is to sit quietly and just watch the plants, insects, birds and other wildlife. Either in a state of careful observation or by just letting your mind wander, you can find steadiness and perspective in the October garden.
Due to the shelter-at-home guidelines, the Master Gardeners have canceled all public events for the time being, but their phone lines are still open: 559-684-3325, Tuesdays and Thursdays between 9:30 and 11:30 a.m.