Your October Garden Checklist for Santa Cruz County
October is the great transition month in Santa Cruz County. The first rains typically arrive by mid-month, breaking the six-month dry season and transforming the garden almost overnight. Daytime highs drop into the mid-60s along the coast and low 70s inland, while nighttime lows settle into the mid-40s. According to UC Master Gardeners, October is the ideal month for planting garlic, California natives, and perennials, since the coming rains do most of the establishment watering for you.
What to Plant in October
Plant garlic. This is the single most important planting task of the month. Separate cloves from the bulb and plant them pointed end up, 2 inches deep and 6 inches apart, in well-drained soil amended with compost. California Early, California Late, Inchelium Red, and Music (a hardneck variety that performs well in mountain areas) are all solid choices.
Direct-sow a second round of cool-season greens if you missed September: lettuce, spinach, arugula, chard, and Asian greens like bok choy and mizuna. These will grow more slowly through the shortening days but will produce all winter along the coast.
Transplant onion starts (Walla Walla, Stockton Red, Yellow Granex) for a late spring harvest. Plant shallots and multiplier onions.
This is the premier month for planting California natives: coyote bush, manzanita, California fuchsia, deer grass, and yarrow. They establish during the rainy season and need minimal irrigation once rooted. It is also prime time for planting perennial herbs: rosemary, lavender, sage, and thyme.
Plant spring-blooming bulbs: daffodils, ranunculus, anemones, and freesia. Tulips and hyacinths need pre-chilling in the refrigerator for 6 to 8 weeks before planting in December.
What to Harvest in October
The last tomatoes, peppers, and eggplant should be harvested before the first rain event, which brings late blight risk. Green tomatoes can be ripened indoors on a countertop (never a windowsill, which gets too hot). Wrap individually in newspaper and check every few days.
Persimmons (Fuyu and Hachiya) ripen this month. Fuyu types are eaten firm like an apple. Hachiya must be fully soft (nearly translucent) or they are painfully astringent.
Pomegranates (Wonderful, Ambrosia) are ready when the skin develops a deep color and the fruit feels heavy. They often split on the tree during rain, so harvest promptly.
Pumpkins should be fully cured and in storage by now. Kiwifruit (a significant crop in parts of the county) ripens in late October.
What to Maintain and Protect
Before the rains arrive, clean gutters and drainage channels around garden beds. Standing water during winter storms damages roots and promotes disease.
Drain and store hoses. Winterize above-ground irrigation if you are in a mountain area where pipes can freeze. Turn off irrigation timers. Let the rain take over.
Rake fallen leaves and use them as mulch or add them to the compost pile. Whole leaves mat down and repel water; shred them first with a mower or by running over a pile in a trash can with a string trimmer.
Apply a thick layer of compost or aged manure to beds that are resting for winter. The rain will work nutrients into the soil over the coming months with zero effort from you.
What to Watch Out For
Late blight (Phytophthora infestans) can devastate tomato and potato plants when the first fall rains combine with moderate temperatures (60 to 70F). This is the disease that caused the Irish potato famine, and it spreads rapidly. UC IPM advises removing and bagging all affected plant material immediately. Do not compost it.
Crane fly larvae (leatherjackets) damage lawns and can chew roots in vegetable beds during wet weather. If you see large clouds of adult crane flies (they look like giant mosquitoes), expect larvae in the soil a few weeks later. Healthy soil with good drainage limits damage.
Roof rats become more active as they seek shelter before winter. Keep fruit trees clean of fallen and overripe fruit. Trim tree branches away from structures by at least 4 feet.
This month: Plant your garlic by October 31. Garlic needs the long, cool growing season from fall through spring to develop full-sized bulbs.
For more help with fall planting, check out our free California Fall Garden Planting Guide at Your Garden Toolkit.
