How to help your roses through the dry summer

How to help your roses through the dry summer It takes strategy to bring roses through drought with their health intact. If you must cut back on landscape watering this summer, you can use this four-part plan--practiced by rosarians in parched Santa Barbara and in Los Angeles--to help roses survive.

Mulch. Around the base of plants, apply a 3-inch layer of organic material such as decorative or shredded bark or commercial compost (in desert areas, use 3/4-inch screened decomposed granite). You'll need about 2 1/4 cubic feet per bush to cover a 3- by 3-foot area.

Don't cover the bud union; if you do, it will be less likely to produce new canes, and canes above the bud union may root, to the detriment of the plant. If soil level is already high near the bud union, scrape away about 3 inches of soil, then replace with mulch.

You can enhance the effect of the mulch by putting down landscape fabric first.

Water efficiently. The roots of a mature rose bush spread through approximately 1 cubic yard of soil, an area 3 by 3 by 3 feet. If your soil is typical (clay loam), 5 gallons of water is enough to wet the root zone. Heavy clay soil holds more water (apply more water less often), sandy soil holds less (apply less water more often).

Apply water directly to the root zone by hand, with a drip system, or by soaker hose. For drip irrigation, use a couple of 2-gph emitters per bush, running the system for 1 1/4 hours to deliver 5 gallons of water to each plant.

If you water with a hose, build a basin around each bush. Turn the hose on, then time how long the hose takes to fill a 5-gallon bucket. If it takes about 30 seconds (typical), count to 30 as you fill the basin around each bush.

To make sure the water you apply wets the soil thoroughly, you can use a wetting agent. Or, to help water linger in the soil longer, you can apply soil polymers. Use a broom handle or soil probe to make 8 holes, each 8 to 15 inches deep, around each bush. Mix a few granules with soil and refill the holes, using no more than 1/4 cup of polymers per bush.

In a pinch, you can use gray water, the wastewater from washing dishes or laundry; roses are quite tolerant of it. Make sure gray water doesn't splash or run off.

Slow growth. Reduce the amount of fertilizer you use by half (or stop feeding entirely where water use is severely curtailed). Instead of deadheading, allow hips to develop from the first spring flowers. Pinch off flower buds that develop from May through August to help induce dormancy.

In inland and desert areas, shadecloth over roses will reduce temperatures and hence the amount of moisture lost.

Reduce foliage. Groom the plant frequently, removing nonessential leaves and stems. Don't let plants get too tall, and remove leaves from around the base.

When you prune, be careful not to promote growth. Always cut to a dormant bud (one that's flattened against the stem) in an older stem, rather than to a swelling bud in a fresh stem.