October Gardening Calendar

October starts warm but ends cool. Toward the middle of the month, nights turn a little crisp and the trees and shrubs begin to glow with the scarlets and golds of autumn. There's even a little rain, but not enough, so watering is still the most important job.

This is prime time to renovate or replace the lawn. If you only fertilize the grass once a year, do it now so it can go into the winter with a healthy system.


Fall means you can plant everything. This is the best time to plant trees, shrubs, vines, and ground covers, especially those that will get only minimum water next season.

Annuals for bloom during the winter and early spring should go in now as bedding plants. Good ones are fairy primrose, snapdragon, stock, viola, pansy, lobelia and calendula. Near the coast you can plant cineraria. Small plants or those planted too late will just sit and sulk until spring before they will put on their show.

Plants from six-packs should be planted only during the first half of the month, after that purchase plants in four inch containers. The only annuals you will be successful at growing from seed will be sweet alyssum and early-flowering sweet pea (if you sow them early).

Annuals placed over bulbs will give a colorful show during the winter before the bulbs pop up. Choose colors that complement the bulbs, such as blue violas with yellow daffodils, salmon  Primula obconica with purple tulips, or purple and white fairy primrose with pink tulips.

Perennials are an excellent buy this month, since the price of a couple of six-packs is only half the cost of one plant in a gallon can next spring.

All of the popular spring-flowering bulbs can be planted this month, but wait to plant the tulip and hyacinth until November or December, since these produce better flowers during the cooler weather.

Use either bone meal or superphosphate in the soil below the bulbs. Our soils are deficient in phosphorus and it is most difficult to get this element down into the root area after the bulbs are planted.

Japanese iris will be arriving in the nurseries this month. This iris does especially well all over Northern California.

If you haven't done so, now's the time to sow cool-season vegetable crops such as beets, cabbage, carrots, chard, lettuce, radishes, spinach, sugar peas, and turnips. Plant garlic bulbs and onions from sets or seeds. Set out young plants of broccoli, Brussels sprouts, cabbage, chives and parsley.


CLEAN, CLEAN, CLEAN. Pull weeds, exhausted annuals and spent vegetables. Rake up leaves and fruits lying on the ground. Load up your compost pile (but not with diseased debris). By removing food and hiding areas you will eliminate many over wintering pests and diseases.

Plant a cover crop if you have any bare soil. A good mix is fava beans, purple vetch, crimson clover, and winter rye (these seeds are available at many local gardening shops, also at Nilsen Feed and Grain on Broadway in Eureka). The first three are legumes that add nitrogen to the soil; the rye adds carbon, which keeps the nitrogen from leaching away. The plants' extensive root growth improves the soil structure. Twice during the winter cut them back to 6 inches, and when the favas (the ones with the big leaves) begin to bloom, cut them down completely. Till them in a couple of weeks later.

Divide perennials and share with your neighbors and friends. I'll bet they're still your friends, even though they pretended to not be home last week and saw you leave that shopping bag full of zucchinis on their porch and slink away (that's the last time YOU plant six zucchini plants). Anyway, cut back the straggly perennials and scratch a little compost into the soil around them.

After dahlia and tuberous begonia foliage dies back, dig up the tubers. Clean and store them in a cool, frost-free place out of the direct sun.

To keep the roses blooming, trim off spent flowers, cutting down to a five-leaflet leaf. Don't prune anything yet. Wounds heal slowly now. Wait until later in the dormant season.

Cuttings should be made of pelargoniums, fuchsias and hydrangeas. In the case of the first two, this is a safety measure, because every so often a severe freeze wipes out your favorites. Use 2- to 3-inch-long tip cuttings of pelargoniums, and hardwood cuttings of the same length for fuchsia and hydrangea.

Be on guard for a resurgence of slugs and snails in cool October weather. Hand pick them or put out bait.

Perfect Partners

There are three plants in my garden that are planted together and they get attention from everyone all year long. Comments are made on the shape, the colors and the fragrances. They are the Lavandula stoechas 'Lavender Otto Quast' also seen as 'Quasti'; Thymus citriodorus (Lemon Thyme); and Origanum vulgare (Oregano).

The lavender is a striking explosion of silver stems and year-round purple bracts and flowers. The thyme and the oregano flowers have similar color and alternate bloom. The lavender is about two feet high and two feet across. The thyme sort of cascades down under it. The oregano is about eighteen inches tall.

These plants are not fussy about soil but require good drainage. I planted the lavender and two thyme plants in a piece of 36" drain pipe about two feet long and set on end. The oregano is planted in a large hollow cinder block set in front of it. They like being watered regularly. Shear the plants in the spring and replant after three or four years because they get burned out and never look as nice again.

Sun angles for October

October sun passage, click to enlargeEnlarge image

During October, at a latitude of 40° north and at solar noon, a board fence six and a half feet high will cast a shadow that is over eight feet long to the north, more so during the the rest of the day. The sun's altitude (elevation) will peak at approximately 37°, or a bit more than a third  of the way up the southern sky.