September Gardening Specifics

September is the beginning of our longest growing season and the most important time to plan for color that will last through late spring. Watch for these annuals as they become available at your local nursery: calendula; candytuft; chrysanthemum (the small bedding type); dianthus; English daisy; Iceland poppies; larkspur; nemesia; ornamental cabbage, kale; pansies; English primrose ; schizanthus; snapdragons; stock; sweet peas (look for early-flowering varieties).

Many varieties of showy perennials will be available in four-inch pots. Plant these perennials (and biennials) for a jump start on permanent color in your garden: Canterbury bells; coral bells; coreopsis; cyclamen (shade); delphinium; dusty miller; foxglove; hollyhock; nicotiana; rehmannia; salvias and Shasta daisy.

For the best selection, buy bulbs now and store them in paper bags or open flats in a cool, dark, dry location until planting time. For best results, hold off on planting until mid-October or early November, when the air temperature is cooler and day length is shorter.

Tulips and hyacinths need to be refrigerated no earlier than Oct. 15 and no later than Nov. 10 and chilled for six weeks to simulate a colder climate. This will get them in the ground when soil temperatures are cooler, giving bulbs a chance to develop a good root system before air and soil temperatures warm up triggering bloom. Look for these bulbs to plant: allium, anemone, crocus, daffodil, freezia, Dutch iris, bearded iris, Persian iris, ixia, leucojum, lycoris, muscari, narcissus, ornithogalum, oxalis, ranunculus, scilla, sparaxis, tulip, tritonia, watsonia, amaryllis. The following bulbs can be potted for indoor color, hyacinth, amaryllis and paper white narccissus can be grown in a soilless mix, like deco rock or pebbles.


Source: Cristin Fusano, Color Specialist/Horticulturist, Sherman Library and Gardens

And General September Care Tips

Plant cool-season vegetables: broccoli, spinach, cauliflower and cabbage. Also plant onions, garden peas, garlic, carrots and beets.

Feed roses and water deeply for beautiful fall blooms.


Thin camellia buds now for bigger and better blooms later. Leave only one bloom per branch to get the largest blossoms. Leave some farther down the stem for later bloom.

The sasanqua camellia is a good choice for the gardener who wants a splash of color in autumn and winter. This first cousin to the better-known camellia japonica has smaller leaves that seem even darker green and waxy with a spectacular display of usually single, small flowers that cover the entire plant.

The sasanqua grows as a sprawling free form or upright. The color ranges of the blooms and the time of flowering varies with the variety. They tolerate more sun than the japonica. They need an acidic soil and must be planted high.

Why book a trip to the Pacific Northwest or the New England states to see autumn color when California gardens can also have beautiful fall foliage? With a little planning, you can have a vivid display of colorful leaves in the fall simply by planting the right kind of trees and shrubs. Three of the more popular trees with show-off color are: Chinese Pistache (Pistacia chinensis), with crimson, scarlet, orange and even yellow-colored leaves; Liquidambar trees with leaf color ranging from burgundy, red, peach, pink, orange, through yellow; and the Maidenhair tree (Gingko biloba), which turns it’s fan-shaped leaves into a luminous yellow display before they drop.


Tend to your roses by removing dead wood, twiggy growth and leaves with spots or mildew. But don’t prune them now.

Before you plant perennials or annuals, prepare the planting bed well: Dig down 18 inches and work in organic matter.

For a “berry” good holiday season, plant berried shrubs for garden color and holiday decorations.

Keep fallen leaves raked off the lawn and out of flower beds. Certain pests love to set up house under them.


A good choice for cool-season color is the bird of paradise.

Source: California Assn. of Nurserymen.