Things to do in September
Add Edibles to the Landscape
Many cool-season vegetables can be tucked into corners of existing beds and borders, transforming a garden into a chic edible landscape. Lettuces are especially adaptable and available in mouth-watering colors that delight the eye and palate. Start seeds in recycled six-packs or four-inch pots for transplanting, or pick up transplants at a nursery. Some eye-catching varieties to consider are mahogany ‘Sea of Red' from Renee's Garden (www.reneesgarden.com) , burgundy tipped mini-romaine ‘Breen' from Johnny's Selected Seeds (www.johnnyseeds.com) and ruffled ‘Lollo Rosso' from Baker Creek Heirloom Seeds (www.rareseeds.com).
Be a Deadhead Fan

In San Diego's mild climate, many annuals and perennials will bloom again with just a little help from gardeners. A key step is deadheading or removing spent flowers. When left on the plant, they send a signal for the plant to set seed and either rest or end its lifecycle. When they are removed, the plant is tricked into overdrive to produce more flowers. On some plants, use your fingers to snap off stems with dead flowers. On plants with many small flowers, like daisies, dead flowers can be removed by giving the plant a "haircut" with sheers or loppers. If the foliage is ratty, cutting back by a third or a half will renew it too. On plants that may be woody at the base, like lavender, avoid cutting back into the wood. After deadheading, a light feeding helps spark new growth.

Camellias
If Camellias haven't set buds give them some 0-10-10 or 2-10-10 and keep the plants moist but not really wet.
Deadhead Roses

'Julia Child'

Enjoy the beauty of blooming roses now through October with a few easy steps, starting this month when spring's first bloom peaks and ebbs. Start by cutting roses either while they are in full bloom to perfume your home or when they are spent and no longer adding beauty to the garden. Both steps are a kind of pruning that will stimulate new blooms. As a rule of thumb, make the cut above a growth node at a five-leaflet leaf pointing outward at a mid-way point on the cane. Cut too high on the cane and the new roses will have weak stems; too low a cut will slow rebloom and may result in an unsightly plant. Feed lightly with an organic or all purpose fertilizer and water deeply. Repeat after each bloom cycle to keep roses flourishing - and flowering in the months ahead.
Drought-Tolerant Plants To Grow

For more than four decades, Mountain States Wholesale Nursery (MSWN) based in Glendale, Arizona, has specialized in desert plants for drought-tolerant gardens. Below are six recent introductions picked by MSWN's local representative Wendy Proud suited for San Diego gardens and readily available in area nurseries.

  • Blue Emu-Bush (Eremophila hygrophana) – An Australian native, this compact shrub to three feet tall and wide can handle heat and cold. Its silvery-white foliage is a dramatic foil for violet-blue tubular flowers that bloom almost year round. Hummingbird magnet.
  • ‘El Toro' Bull Grass (Muhlenbergia emersleyi ‘El Toro' – Bull grass is native to the rocky oak woodlands of Arizona and Texas. This variety is prized for its blue-green leaves and purple-tinged rosy panicles that appear in the fall and turn straw-colored in winter. Grows in dense clumps to 3 feet tall. Sun or part shade; very drought-tolerant.
  • ‘Yellow' Yucca (Hesperaloe parviflora ‘Yellow') – Like the familiar red-flowered form of this tough yucca, the arching foliage on this variety is dark green with curled slender white threads along the edges. But its flowers on spikes that rise up to six feet tall are a soft yellow. Likes full sun, well-drained soil and minimal water once established.
  • Damianita (Chrysactinia mexicana) –Sunny yellow daisies top this compact mounding shrub in spring and fall. The Texas native is also famed for its aromatic dark green foliage. Grows to two feet tall and wide in full sun;  drought tolerant once established. Can become woody over time.
  • Purple Prickly Pear (Opuntia ‘Santa Rita Tubac') – A must-have for cactus collectors, purple prickly pear shows off pads washed in shades of lavender in winter. As temperatures warm, the pads turn a soft blue-green. Spring flowers are golden yellow. Grows to 6 feet tall in full sun. Plant away from high-traffic areas.
  •  Phoenix' Mesquite (Prosopis hybrid ‘Phoenix') - This hybrid combines the desirable traits of a strong grafted root system, thornless branches and slow growth. Vase-shaped and often multi-trunked, it grows up to 30 feet tall. Yellow flowers in spring.
Feed Vegetable Plants
Fast-growing vegetables need regular feedings of nitrogen to thrive. For every 10 feet of row, apply one-third to one-half cup of ammonium sulfate or one-fourth cup of ammonium nitrate alongside the row a few inches from the plants and then irrigate thoroughly. Apply when corn is six inches tall and then again when it is 24 inches tall; when cucurbits begin to produce runners; when eggplant, peppers and tomatoes begin to bloom and again one month later; and for beans, a month after planting or when runners start to climb.
Fruit Trees and Vines
  • Continue periodic, thorough irrigation to maintain adequate soil moisture until winter rains begin.
  • Operate drip irrigation systems until we receive at least two inches of rain; this helps prevent salt injury.
  • Prune out dead and severely damaged shoots of deciduous trees before foliage drops.
  • Cover grape clusters with paper bags (poke small holes for ventilation) to protect maturing fruit from yellow jackets and birds.
  • Check on maturity of kiwi fruit. Maturity is measured by a change in seed color from white to brown or black. Pick large fruit first, but harvest before fruit softens.
Get Landscape Design Advice
Shocked by high water bills? Determined to transform your garden into a waterwise landscape but not sure where to begin? Jump-start your makeover with a professional landscape design consultation at The Water Conservation Garden. The 45-minute sessions are with consultants who specialize in drought-tolerant landscapes. Homeowners bring photos and dimensions of a targeted area; they leave with a design plan and plant list. Cost is $75 ($60 for garden members). Call (619) 660-0614, ext. 10, to learn dates and availability.
Grow Bulbs Suited to Southern California

Yes, tulips and daffodils will grow here, but why be limited to these traditional bulbs when there are many others ideal for our Mediterranean-style climate. Here are some selections from Jim Threadgill of Easy To Grow Bulbs in Oceanside (www.easytogrowbulbs.com ).

  •  Watsonia - These South African natives are becoming known as the gladiolus of Southern California. Flower spikes 3-4 feet tall rise above sword-like foliage. Fragrant blossoms range from pure white and cherry red to pastels and bicolor. Will naturalize.
  • Freesia - Another South African native, freesias are prized for their fragrance and rainbow of colors. Flower stems grow 18 inches tall, making these plants ideal for edging borders. Look for new shades of blue and bicolor combinations. Naturalizes.
  • Spanish Bluebell (Hyacinthoides hispanica) - Some consider these natives of Spain as hyacinth substitutes for their blue flowers on sturdy stems up to 20 inches tall. Unlike hyacinths, the bell-shaped blossoms are not scented. ‘Excelsior' is a popular dark blue hue.
  • Golden Dawn' narcissus - This tazetta hybrid is among a group of narcissuses that are ideal for mild winter climates. Yellow with a dark gold cup, multiple flowers top each stem. The scent is sweet and not as powerful as the familiar ‘'Paper White' tazetta. Plus the bulbs are deer, gopher and rat proof.
  • Giant White Squill (Urginea maritima) - This Mediterranean monster of a bulb - each can weigh 6 to 8 pounds - performs like the familiar naked lady (Amaryllis belladonna). Foliage appears first, lasting November to April, and then dies back, making way for towering flower spikes to 6 feet in September. Each is covered with thousands of small white flowers that open from top to bottom for a month. Avoid excess summer water.
  • Saffron Crocus (Crocus sativus) - Plant these fall-blooming crocus in October and they will bloom by Thanksgiving. Low growing, the  lilac flowers are the source of saffron used in cooking. Harvest and dry the orange-red stigmas for use in paella and other dishes.
  • Eremurus – Four to 5-foot tall flower spikes gave this Asia native its common name of foxtail lily or desert candle. ‘Cleopatra' has orange sherbet flowers, while the Shelford hybrids are a mix of pastels. Handle brittle roots carefully when planting.
  • Trumpet Lilies - Stems can top 6-feet tall when these bulbs, also known as Aurelian hybrids, burst into bloom in late spring. Locate them to enjoy their rich perfume. Trumpet blooms with bold stamens are golden apricot on ‘African Queen', lemon-yellow on ‘Golden Splendor' and rose on ‘Pink Perfection'.

Threadgill recommends planting in October as the soil cools. If purchased in advance of planting, store in a mesh or paper (not plastic) bag in a cool, dry location.

Grow More Veggies

Tomato 'Aussie'

More urban farmers tend tomatoes than any other vegetable. But there are many other vegetables and herbs to try during San Diego's warm growing season. Add the classic Genovese-type basil and some sweet bell peppers for a pizza garden. Handsome eggplant plants bear pretty lavender flowers as well as colorful fruit, while a couple zucchini plants handily feed a family all summer. If space is available, plant an artichoke with its dramatic silvery leaves on a plant that can soar to 4 feet or more tall and wide. Explore more options in the Master Gardeners' cool and warm season vegetable planting guide that also includes recommended planting times along the coast and inland. Visit www.mastergardenerssandiego.org and click on Resources. Another good guide is "Sunset Western Garden Book of Edibles."

Harvest Homegrown Crops

To enjoy the full flavor of vegetables grown in your garden, don’t allow them to linger too long on the vine. In just a few days, zucchini go from tender and tasty to tough and bland. Harvest daily to savor cukes, beans and squash while they are still young. Pick corn when the silk turns brown and juice in the kernels is milky and sweet. Ripe melons literally fall off the vine. Eggplant should be shiny and purple-black. Pinch flowers off basil and other herbs to keep them at their culinary best. Visit the UC Davis’ Vegetable Research Information Center (vric.ucdavis.edu ) , for details on planting and harvesting more than two dozen edibles.

Lace trees

Beautify landscape trees and reduce the risk of wind damage with an annual "lacing," skillful and artistic pruning to reveal a tree’s structure and allow wind to pass through. Gardens also may benefit from added filtered sunlight. Certified arborists will know the best time of year to "lace" individual trees. They also can help save trees severely damaged by wind or fire. To find a certified arborist in your area, see the website of the Professional Tree Care Association of San Diego County, www.ptcasandiego.org and the International Society of Aboriculture, www.isa-arbor.com

Learn More about Lei Flowers
Bring the unmistakable scent of Hawaii to your garden with the addition of  Plumeria rubra. This tropical plant loves the sun and thrives on infrequent deep watering (overwatering will kill it). The highly fragrant star-shaped flowers, used in leis, vary from ivory whites to warm yellows, pinks, rosy reds and multicolored pastels. See (and smell) plumeria's many variations at the annual show and sale of the Southern California Plumeria Society on in Balboa Park Sept. 1-2. More information is at www.socalplumeriasociety.com
Make-Over Veggie Gardens
Warm season vegetable gardens often are ready for a makeover this month. (Coastal gardens may be the exception, where mild conditions continue into October.) To get ready for cool-season crops, remove spent plants and clean up all debris that may harbor pests or diseases. Then boost the soil with compost and a slow release fertilizer high in phosphorus. If planting in containers, replace at least half of the soil with new potting mix. Toward the end of the month, cool season veggies can be planted, including broccoli, carrots, peas, spinach and lettuce.
Mulch
Clear up weeds and mulch ornamental beds.
Oleanders Under Attack

Tough, waterwise and carefree oleanders all around the county are falling victim to an incurable bacterial disease. Oleander leaf scorch, which blocks nutrients and water flow from the roots to the leaves, is spread by the same glassy winged sharp shooter that carries the grape-vine killing Pierce's disease. Leaves on infected plants turn yellow and die, a process accelerated by hot, dry weather. Affected branches can be pruned out, but doing so will not save the plant. Gardeners forced to replace dead or dying oleanders used as hedges or screens might consider purple hop bush (Dodonaea viscose ‘Purpurea'), lavender starflower (Grewia occidentalis), or ‘Long John' Grevillea). Replanting oleanders again is not recommended since the new plants may be felled by the same disease. More information is at the Pest Note "Oleander Leaf Scorch" at www.ipm.ucdavis.edu.

Order Wildflower Seeds

Fall and winter rains bring poppies and other native wildflowers to life early in the new year. When a soaking rain is due, be prepared to sow seeds for the state flower, tidy tips, baby blue eyes and more. For decades, the Theodore Payne Foundation has been an excellent source of all-native California wildflower seeds. Choose from mixes designed for coastal, inland or mountain gardens or from original mixes developed by Payne, a pioneering nurseryman in Los Angeles. Purchase a packet or pound at www.theodorepayne.org, where you'll also find plenty of seed sowing tips. Store seeds in a cool, dry, dark place until time to plant.

Pick, Prune, Mulch
In this transition month from summer to fall, continue to harvest warm-season crops to keep tomato, squash, beans and other plants producing as long as possible. Spent veggie plants, on the other hand, should be pulled and composted. Heat-loving summer annuals get the same treatment – pruned if performing, yanked if not. Don't plant any more regardless of how tempting they look in nurseries now. Cut-back summer blooming perennials to remove spent blooms; some will bloom again as mild weather returns. Avoid pruning spring bloomers now; many will already be setting buds for next season's display.
Plant and Care for Oranges, Lemons and Limes

Start or add to your citrus orchard this month when conditions are generally ideal for planting. Oranges, lemons and limes thrive throughout the county; grapefruit and tangelos do best inland. Pick varieties hardy in your area and plant in full sun in well-draining soil. Dig a hole as deep as the root ball, but twice as wide to encourage wide ranging feeder roots that grow close to the ground's surface. After citrus is planted, proper irrigation is key. The root ball needs to be kept moist until roots grow out into the soil. But over watering can cause rot and other diseases. Start by watering at least once a week, more often in times of extreme heat or dryness. Increase the interval as the tree matures. As the trees grow new leaves or blossom, adequate regular watering also can help prevent leaf and blossom drop. Regular water too helps prevent fruit splitting in navel oranges that commonly occurs in fall. How to judge water needs? Check moisture levels about 2-inches below the surface. When dry to that depth, water again.

Prune Trees "Up"
In a roaring wildfire, low-hanging branches can turn trees into torches in a matter of minutes. Early this month, as part of creating defensible space around your home, "prune" up trees, removing branches 6 feet or less from the ground. Branches overhanging the roof or eaves also should be removed, along with any dead wood. Wood saved for kindling should be stored well away from any structure. If possible, water trees deeply; the extra moisture adds to their fire-resistance, especially at the end of a particularly hot summer.
Reading, Writing and Gardening
If your son's or daughter's school doesn't have a school garden, the Master Gardeners Association can help you and the school's teachers get one growing. Master Gardener volunteers are consulting with educators and parents to plan, plant and care for more than 100 school plots that teach gardening essentials and the pleasures of homegrown produce. A detailed guide, "Plant a Seed, Watch It Grow," is on the Master Gardener Web site, along with information on grants, a list of existing school gardens to visit, and forms to request help getting started. Find it all at www.mastergardenerssandiego.org.
Remove branches properly
If an unsightly, diseased or broken tree branch needs to be removed, take care to protect the tree from harm. Improper pruning can make trees vulnerable to disease and pest infestations. Start by shortening the branch to a stub about a foot long. Make a cut on the underside of the branch about a third of the way through; then about an inch further out, on the top, make a second cut, cutting until the branch breaks off. Then make a final cut to remove the stub, taking care not to cut into the collar where the branch joined the trunk of the tree. Eventually this "wound" will be sealed off by callus tissue. A diagram is in "The Sunset Western Garden Book."
Resources for Water Management

When desert winds blow, water loss from plants and the soil, called evapo-transpiration, soars. Plants may wilt, lawn grass may lose its resiliency and leaves on trees may curl and drop. Water conservation sites, like www.bewaterwise.com , post daily calculations that can help homeowners plan and adjust irrigation to meet the landscape's ever-changing needs. The higher the reading, the more water plants require. Container plants, including succulents, are especially vulnerable and will need increased water during heat waves or Santa Ana events. So will gardeners; if you're working outside, stay well hydrated.

Rose Slug Remedies
carrot

There's no mistaking the toll of voracious rose slugs. Shiny new leaves are perforated with holes or stripped of green leaving behind a lacy brown skeleton. The culprit actually isn't a slug, but the larvae of sawflies, tiny wasps. Sawflies lay eggs on the underside of leaves and when they hatch, the larvae feed there. At the first sign of damage inspect leaves for the light green caterpillar-like larvae about 1/2-inch long.  For minor infestations caught early, remove affected leaves and crush any larvae. Larger numbers can be treated with strong sprays of water to the underside of leaves or a coating of horticultural oil, neem oil or insecticidal soap. None of these treatments harms bees or other beneficial insects. Because this is not a caterpillar, Bt (Bacillus thuringiensis) is not effective.

Roses
Time to clean up rose bushes, water well and fertilize for fall blooms.
Vegetables
  • Remove warm-season vegetables badly damaged by pests or diseases or past their prime production periods.
  • Prepare the soil for planting cool-season vegetables by incorporating composted organic matter and a pre-plant fertilizer high in phosphorus. Begin planting cool-season vegetables: broccoli, Brussels sprouts, beets, cabbage, carrots, cauliflower, endive, fava beans, kale, kohlrabi, lettuce, parsley, peas, potatoes (white), spinach and turnips.
  • Buy seeds of short-day onion hybrids (Grano or Granex), as well as garlic cloves to plant in November for bulb production next summer. Onion sets can be planted for a quick crop of green onions, but not for bulbs.
  • Dig sweet potatoes before any danger of frost. Be careful not to bruise roots. Dry thoroughly (one or two weeks), wrap in newspaper and store close to 60 degrees Fahrenheit.
  • For information about Asian citrus psyllid go to www.Californiacitrusthreat.org.