To Do In Your Garden for September: Southern California

September Garden Tips (for more great information visit www.AndersonsLaCostaNursery.com)

Unwritten rules of gardening ... The best way to garden is to put on a wide brimmed straw hat and some old clothes and with a hoe in one hand and a cold drink in the other tell your husband where to dig.

The most important tip this month - Protect Against Wildfire: September is the start of the Santa Ana wind season. If you live in an area that is prone to wildfires you should prune off dead tree limbs, clean your yard of brush and dead leaves and clean leaves from the roof and gutter.

 

September is our transition into Fall here in Southern California and the start of the best planting season of the year (according to the resident self appointed expert - Dave). Although the nights may begin to cool off the days are still warm and it's not uncommon to have short blasts of extremely hot weather and Santa Ana winds (see info below on clearing the garden/yard in case of wildfires).

 

Over the next two or three months we switch from summer-blooming to winter-blooming annuals and from warm-season to cool-season vegetables. This is not an abrupt change but a slow transition. Start cleaning out faded flowers and vegetables but leave the good ones in place to enjoy as long as they last.

 

If in August you did not sow seeds for transplants - do it now. Now is the time to prepare the soil and to begin to plant but don't rush the planting at the expense of preparing your soil well. Remember - October is the best month for planting so you have time. The basis for every good garden is the soil; if you take care of the soil you won't have to worry about the plants. The steps differ depending on whether you're starting a new planting bed or replanting an existing one. If you've never planted a fall garden before and if you choose to do it this year you'll be in for a most rewarding experience.

 

Autumn is the time to plant the cool-season annuals, perennials and vegetables all of which will thrive in our lovely San Diego-area autumn weather. Our autumn weather is not only a boon for our plants but it's also probably the most pleasant time of the year to be out working the garden. It is the very best time of the year to plant most trees and shrubs. By planting them in the fall they have time to develop a strong root system for their later bloom period.

 

Start by turning the soil and watering deeply - continue to water and wait at least two weeks. The loose soil and water should germinate most of weed seeds in the soil. Weed these opportunists out now and you should have an easier time keeping the bed weed-free later. Before planting, finish with the soil preparation steps for existing beds which follows.  

 

 

Loosen the soil and add a three-inch to four-inch layer of organic material. This can be home-made compost, bagged compost or planting mix. Add an all purpose food and turn in well. If you have a heavy clay soil (as most of us do) add some gypsum; it helps to break up the clay (about 10 pounds for every 100 sq. ft). To replenish the nitrogen in the soil, add bloodmeal, cottonseed meal or some well-composted manure. To replenish the phosphorus in the soil add phosphate or bone meal (Note: Since phosphorus is water-insoluble and nearly immobile in the soil it should be added now when it can be thoroughly mixed into the soil). To figure out how much of each of these amendments you should add follow the instructions on the label. When all the amendments have been added mix them thoroughly into the soil with a spade or spading fork. Now you're ready to plant.  

 

Loosen...Add organics...Add gypsum (if needed)...Add nitrogen...Add phosphorus...Mix thoroughly...Start planting!

 

Sweet Peas: For sweet peas by December plant seeds now. Look for varieties designated "early flowering." Spring or Summer-flowering types won't bloom until the days are more than twelve hours long. To speed germination soak seeds overnight before planting. Provide a trellis for vines to climb.

 

Peas: Choose a good variety. There are three basic types of peas: snow peas, snap peas and English peas. The first two have edible pods - English peas have to be shelled. Peas need a trellis for vines to climb.

 

Cool-season Vegetables: Plant cool-season vegetables such as broccoli, brussel sprouts, cabbage, cauliflower, celery, kale, kohlrabi, mustard, lettuce and other greens.

 

Cool-season Flowers: Plant cool-season flowers including calendula, cineraria, dianthus, delphiniums, Iceland poppies, nemesia, pansies, snapdragon, stock, wild flowers, violas and violets.

 

Amaryllis Belladonna: Dig up and divide Amaryllis belladonna (Naked Ladies) after they bloom but before new roots and foliage have begun to grow. If the bulbs are transplanted during this brief period of dormancy next year's flowering will not be interrupted.

 

Cut back flowered ornamental grasses to 1.5" (that's not a typo - 1.5 INCHES) tall by November (or sooner). 

 

Camellias:  Keep camellias well watered this month. Letting them go dry will cause the buds to drop off depriving you of their beautiful blooms.Some varieties of camellias form a great many more buds than they can support and so will naturally drop buds. The naturally-dropped bud will be green whereas a water-stressed plant will drop brown buds. For the largest flowers, you can start "disbudding" camellias now by removing all but one flower bud from each cluster. Be careful not to remove the growth bud. Growth buds are thin and pointed; flower buds are round and fat.

 

Citrus: Make sure citrus trees are adequately and evenly watered during this month. If the roots go dry the result can be split fruits.

 

Cymbidiums: Switch cymbidiums to a lower nitrogen, higher phosphorous & potassium fertilizer to encourage development of bloom spikes. If your cymbidium leaves are dark green chances are that they're in too much shade. Bring them out into more light until their leaves turn a yellowish color.

 

Hydrangeas: If you want to maintain a "blue" hydrangea or change your hydrangea's color you need to start now. Once they start developing buds it's too late. Not all hydrangeas can be made blue. White varieties always stay white and some pinks turn purple instead of blue. The "flowers" on your hydrangea are really modified leaves called bracts just like the so-called flowers of poinsettias. The hydrangea bract color can be modified by adjusting the pH of the soil. A pH 4.5 to 5.0 yields blue flowers, a pH 5.5 to 6.5 yields mauve, and a pH 7.0 to 7.5 yields pink. Hydrangea Blue can be used to lower soil pH. Liberal use of compost will also aid in reducing soil pH.

 

Irises: Clean up the iris beds now. Cut off damaged leaves, remove debris and mulch beds. Irises will not bloom if over-crowded and need to be divided about every three years. If your irises need dividing - do it now.

 

Oleanders: Oleanders can be pruned now after bloom. Pruning in the Spring instead of the Fall may reduce Spring bloom. Prune oleander back severely, don't chop off tops like a hedge. This fails to renew the plant and all you get is an unattractive hedge with no flowers.

 

 

September Fillers

Bedding plants are those "sure bets" the gardener can count on for fall and winter color especially when little other color has been planned on from the shrubs, trees or perennials. Among those popular bedding plants are the pansies which give color from the day they are planted either as a riot of mixed colors or massed together in solid shades of blue, yellow, white, red, rose and pink.

 

Another great addition to the flower bed is the fairy primrose which has a dainty flower with delicate foliage. These flowers provide a choice from white, pink, rose, red or lavender. For a mass of color around the borders and edges try the viola. Its cheerful flower is available in purple, white, yellow and blue.

 

For a taller flower try some snapdragons. They come in heights from 8 inches up to 2 1/2 feet tall. They make excellent cut flowers. If they are not in stock by the weekend they will arrive early in September.

 

In California there are two major planting seasons--spring and fall. Spring gets plenty of attention but one of the best kept secrets is the beauty of fall planting. First of all is the weather. Its cooler in the fall and that makes it easier to transplant trees, shrubs, bedding plants and to plant lawns. Although trees and shrubs are not actively growing above the ground they are very busy sending out strong roots and getting themselves established for the spring and summer. It's easier to prepare the ground for major plantings too so go ahead and discover the growing possibilities for your garden this fall. You'll reap the benefits in the spring. Just because the tomatoes are slowing down their production doesn't mean you can't have fresh home grown vegetables in the winter. Prepare the vegetable plot and get ready for winter vegetable gardening.  

 

Roses should be encouraged to continue blooming by making sure they get the supplemental food they need. Feeding them becomes the number one item if gardeners want to have cut roses in their home during October, November and maybe even December. This feeding doesn't guarantee roses for Christmas but without it the possibility will definitely be eliminated. The last meal for the roses should be in early September - no later than mid-month in most areas. A later feeding may stimulate too much growth at the time when roses should be slowing down and taking a rest.

 

If you're expecting guests for the winter holidays from the East Coast or Midwest and you want to impress them with your winter flower garden start planting the winter annuals after the middle of this month. Pansies, stock, Iceland poppies, California poppies and calendulas should all be in glorious bloom in time for the holidays when they are planted this month.

 

Planting At The Correct Time: When transplanting cool-season flowers and vegetables you can avoid stressing the plants by setting them out on a cloudy day or in the late afternoon to avoid the wilting affect of direct sunlight. Water plants the day before transplanting and water immediately after planting. If rain is forecast set your plants out just before it is supposed to begin.

 

Give Garden A Fall Cleaning: Don't neglect your fall cleanup chores. Spent annual flowers and vegetables should be removed immediately; pests and diseases thrive in plant debris. You will be surprised how a thorough garden cleaning will reduce insect problems.  

 

Flowers From Seed: these can be planted any time this month: African daisy, Alyssum, Bachelor button, Bells of Ireland, Calendula, California poppy, Candytuft, Canterbury bell, Carnation, Chrysanthemum, Cineraria, Clarkia, Columbine, Delphinium, Forget-me-not, Foxglove, Gerbera daisy, Godetia, Hollyhock, Iceland poppy, Larkspur, Linum, Mignonette, Nicotiana, Pansy, Phlox, Scabiosa, Shasta daisy, Snapdragon, Stock, Sweet pea, Sweet William, Verbena, Viola, Wildflowers Flowers

 

For Bedding Plants: Wait until the weather cools toward the end of the month to set out transplants for these plants: African daisy, Alyssum, Calendula, English daisy, English primroses, Gerbera daisy, Iceland poppy , Pansy, Penstemon, Primula malacoides, Snapdragon, Stock, Viola Vegetables: Beets, Broccoli, Brussels sprouts, Cabbage, Carrots, Cauliflower, Celery, Kohlrabi, Lettuce, Oriental greens, Peas, Potatoes, Radishes, Spinach, Sugar snap peas, Turnips.