As the weather cools in the fall, the last of the year's roses bloom. (Photo: Jeannette Warnert)

Tasks

• Adjust watering systems as weather cools.
• Remove and dispose of any fruit and nuts that cling to the tree.
• To discourage spider mites, spray hedges and shrubs with water to clean them and keep them free of dust.
• Water citrus, being careful not to overwater. Continuously wet soil risks root rot.

Pruning

• Do not apply any treatments to pruning cuts or other wounds because these materials are ineffective (and often detrimental).
• Deadhead and shape rosebushes to promote a final fall bloom.

Fertilizing

• Wait two weeks after planting new flowers and vegetables before feeding with organic or complete fertilizer.
• Add bulb fertilizer to planting hole before planting bulbs.

Planting

• This is the best time to plant shrubs and groundcovers.
• Groundcovers: Carpet bugle (Ajuga), Germander (Teucrium chamaedrys ‘Nanum').
• Perennials: Cyclamen, French tarragon (Artemisia dracunculus), cranesbill (Geranium).
• Before planting winter vegetables, turn a generous amount of compost into the vegetable bed.
• Fruits and vegetables: garlic, onion sets, lettuce, parsley.
• Trees, shrubs, vines: Acacia baileyana, strawberry tree (Arbutus ‘Marina'), hawthorn (Crataegus), sago palm (Cycas), desert willow (Chilopsis linearis).

Enjoy now

• Annuals and perennials: vinca (Catharanthus), chrysanthemum, dianthus, coneflower (Echinacea), globe amaranth (Gomphrena).
• Bulbs, corms, tubers: dahlia.
• Trees, shrubs, vines: pineapple guava (Feijoa), morning glory (Ipomoea), crape myrtle (Lagerstroemia).
• Fruits and vegetables: almonds, lettuce, melon, nectarines, persimmon.
• Fall color: goldenrain tree (Koelreuteria), sweet gum (Liquidambar styraciflua).

Things to ponder

• Do not replace vinca with pansies in the same bed, due to a soil borne fungal root rot that affects these plants.

Chitalpas are decidious trees that bloom for several months during the summer. They can be planted this time of year. (Photo: Wikimedia Commons)

Tasks

• Repair damaged spots in cool-season lawns (such as tall fescue) by scratching with a rake, seeding and covering with mulch. Keep moist until the new grass seedlings are well established. Warm-season lawns like Bermuda grass will soon be entering their dormant season, so bare patches should be covered with mulch to discourage winter weeds.
• Use spent vegetable plants and summer annuals to start a compost pile.

Pruning

• Divide and thin perennials.
• Sharpen your pruning tools in preparation for fall pruning.

Fertilizing

• To avoid a flush of new growth late in the growing season, do not apply fertilizer to citrus, avocados or other frost?tender plants.

Planting

• If the weather is cool enough, plant spring bulbs and annuals.
• Annuals: calendula, Canterbury bell (Campanula), pansy (Viola).
• Perennials: catmint (Nepeta), dianthus, fortnight lily (Dietes), Lantana.
• Fruits and vegetables: broccoli, cauliflower, parsley.
• Trees, shrubs, vines: barberry (Berberis), redbud (Cercis), fringe tree (Chionanthus), chitalpa.
• Tender leafy vegetables are best planted later in the month, and even then may require daily watering until they are well established.

Enjoy now

• Annuals and perennials: fibrous begonia.
• Bulbs, corms, tubers: cyclamen.
• Trees, shrubs, vines: beautyberry (Callicarpa), bottlebrush (Callistemon), chitalpa.
• Fruits and vegetables: garlic, gourds, grapes, peaches.
• Fall color: Raywood ash (Fraxinus angustifolia), maidenhair (Ginkgo biloba).

Things to ponder

• Cover remaining tomato and pepper plants with a garden blanket to extend the harvest season into November.
• Limit the size of fall vegetable gardens to avoid over-production. Plant only the varieties that you know you will use and enjoy, or that you can share with others.

Be mindful of changing irrigation needs as days get shorter and temperatures begin to drop. Adjust automatic timers accordingly. (Photo: Jeannette Warnert)

“A garden is a thing of beauty and a job forever” ~ Richard Briers

Tasks

• Despite a few last very hot summer days, fall is rapidly approaching with shorter days and cooler nights. Adjust irrigation timers, as your garden requires less water.
• The cooler weather is perfect for working in the garden. Start fall cleanup.
• Deeply water fruit and nut trees. Ideally, mature fruit trees should be irrigated to a depth of 3 feet.

Pruning

• Prune and shape photinia now to avoid removing the attractive new, red foliage. Photinia can be pruned aggressively if the plant has grown too large.
• Finish dividing iris. Replant while conditions remain warm and dry, and share extra rhizomes with friends and neighbors.

Planting

• Bulbs that do not need chilling may be planted beginning this month.
• Plant winter and spring annuals and cool-weather vegetables from cell packs.
• Annuals: snapdragon (Antirrhinum), English daisy (Bellis perennis).
• Perennials: Alstroemeria, Bellflower (campanula), chrysanthemum morifolium, Geum.
• Fruits and vegetables: beets, carrots - plant from seed.
• Trees, shrubs, vines: abelia, acacia, horse chestnut (Aesculus), strawberry tree (Arbutus unedo).

Enjoy now

• Annuals and perennials: alstroemeria, yarrow (Achillea), aster, begonia.
• Bulbs, corms, tubers: canna.
• Trees, shrubs, vines: barberry (Berberis), bougainvillea, butterfly bush (Buddleia davidii).
• Fruits and vegetables: almonds, beans, corn.
• Fall color: maple (Acer), cotoneaster.

Things to ponder

• A thick layer of mulch acts as insulation. If applied while the soil is still warm (55°- 65°) it can help extend the fall growing season.
• In the absence of soaking rains, continue to deep water trees and large shrubs at least once a week.

Consider a water-permeable patio, which is less likely to result in backyard water runoff. (Photo: Jeannette Warnert)

Tasks

• Clean up around the base of fruit trees, and compost or dispose of all fallen fruit and nuts.
• Apply preemergent herbicide in early September to prevent winter weeds.

Pruning

• While cutting and deadheading roses, prune lightly to shape bushes and encourage fall bloom. Always prune to an outward facing bud.

Fertilizing

• Fertilize fruit and nut trees following harvest.
• Fertilize roses for fall bloom.

Planting

• The fall planting season begins in September – wait for cooler days for best results.
• Perennials: Coneflower (Echinacea), rosemary (Rosmarinus), Mexican blue sage (Salvia leucantha), thyme.
• Annuals: Iceland poppy (Papaver nudicaule), sweet pea (Lathyrus).
• Bulbs, corms, tubers: grape hyacinth (Muscari), narcissus, ranunculus, squill (Scilla), tulip, Watsonia. Purchase bulbs by Labor Day, plant by Thanksgiving.
• Fruits and vegetables: Asian greens, radish, spinach, sugar snap peas (plant from seed)
• Trees, shrubs, vines: Abelia, Forsythia, palo verde (Parkinsonia), viburnum, xylosma.

Enjoy now

• Annuals and perennials: petunia, gloriosa daisy (Rudbeckia), marigold (Tagetes).
• Bulbs, corms, tubers: fairy lily (Zephyranthes), dahlia.
• Trees, shrubs, vines: cape plumbago, rose, chaste tree (Vitex).
• Fruits and vegetables: apples, pistachio, plum, squash, tomatoes.

Things to ponder

• Chill tulip and hyacinth bulbs in the refrigerator for 6 to 8 weeks. Do not store apples or ripe carrots in the same area.  Plant in early winter (October-November) after garden soil has cooled.
• Dust on leaves reduces the effectiveness of foliar fertilizers, pesticides and herbicides. Before spraying, shake, brush or rinse dust off plants.
• If installing a patio or other hardscape, choose water-permeable materials if possible.