September Sunny days still bring the heat, but cooler nights hint of things to come. It’s time to dig out your gardening tools! PLANT Plant citrus while the weather is still warm. Choose varieties that are better adapted to desert conditions. Plant strawberry varieties that perform in low-desert conditions. Choose a location that has protection from afternoon sun. Plant fall herbs such as chives, thyme, catmint, cilantro, cumin, dill, fennel and parsley. Transplant herbs such as lemongrass, marjoram, mint, oregano, rosemary, sage and thyme. PREPARE Dig compost into vegetable beds. Rearrange container plants to sunnier locations as the sun’s arc slips southward. Chill tulip, crocus, daffodil and hyacinth bulbs in the refrigerator for eight weeks prior to planting. PRUNE Cut back summer tomatoes and peppers that made it through the summer to promote a new bloom before frost. Trim roses and remove dead twigs to promote a second bloom in the fall. Prune shrubs such as oleander, privet, xylosma, Texas ranger and Arizona rosewood that have become overgrown. WATER Cut back on water for deciduous fruit trees, grape vines and citrus to slow growth and get ready for cooler temperatures. Water citrus deeply out to the plant’s canopy every two weeks. SOW At the end of the month, sow seeds of arugula, beets, bok choy, radish, carrots, kale, kohlrabi, leeks, lettuce, cabbage, peas, turnips, spinach, broccoli and Swiss chard. MAINTAIN Hose off dusty plants to control spider mites. Divide iris this month. Dig up large clumps and cut rhizomes into small pieces. Pull and compost the last of the summer annuals. Refresh garden beds by incorporating four to six inches of organic matter. FERTILIZE Fertilize with nitrogen in early September to provide nutrients to summer-stressed plants. Water the day before and after applications to prevent burn. Feed roses with a slow-release fertilizer that will last through fall. Fertilize citrus with the third and final application of nitrogen for the year. Add organic nitrogen sources to the soil, including alfalfa meal, blood meal, coffee grounds, cottonseed meal, fish emulsion and guano. TIP OF THE MONTH A little extra care will keep non-woody annuals and perennials looking their best. Trimming back growing tips will make plants less “leggy.” Use your thumb and forefinger to pinch back soft plants such as petunias several times during the growing season. Use pruners on sturdier perennials, which may only need a trim once or twice during the peak season to keep their shape more compact. Deadheading spent blooms also will keep plants looking neater and will promote abundant flowering.