What to do in your garden in May

Planting and Shopping

Plant blossoms for butterflies. These drought-tolerantplants bear flowers that will attract butterflies to your garden:Angelita daisy (Tetraneuris acaulis), blue mist spirea (Caryopteris x clandonensis), butterfly weed (Asclepias tuberosa), English lavender (Lavandula angustifolia), Gaura lindheimeri, gayfeather (Liatris punctata), blue-flowered germander (Teucrium orientale), globe thistle (Echinops bannaticus), indigo bush (Dalea pulchra), Maximilian sunflower (Helianthus maximilianii), New Mexico hummingbird mint (Agastache neomexicana), Pitcher’s blue sage (Salvia pitcheri),Sedum sieboldii, and sulfur flower (Eriogonum umbellatum).

Set out or start summer color. At lower elevations, plantseedlings of these heat-loving flowers: ageratum, cosmos, globeamaranth, marigold, portulaca, Salvia farinacea, strawflower (Helichrysum), sunflower, vinca (periwinkle), and zinnia. Athigher elevations, start seeds of these flowers indoors fortransplanting after June 1: cosmos, Iceland poppy, lobelia,nasturtium, painted tongue (Salpiglossis sinuata), pansy, petunia, schizanthus,snapdragon, and sweet William.

Shop for irises. See hundreds of irises in bloom and pickout your favorites at Long’s Iris Gardens in Boulder, Colorado (9-5 daily Apr 30-Jun 12; 303/442-2353 for catalog with drivingdirections). Designated fields are open for digging irisrhizomes on a cash-and-carry basis. Tools and storage bags areprovided. Rhizomes are also available by mail order. When choosingirises, extend the bloom season in your garden by choosing kindsthat bloom at different times. At Long’s, miniature types bloom inearly May, intermediates at midmonth, and tall bearded types inlate May and in June. Plant irises in full sun; set rhizomes barelybelow the soil surface.

Maintenance

Choose sensible containers. Before planting summer flowersand vegetables, keep in mind that larger containers retain soilmoisture longer than smaller ones. Those made of plastic dry outless rapidly and are much lighter than those of terra-cotta orwood. If you use containers made of those materials, try nestingthe container in a plastic liner to conserve moisture. Fill thecontainer with a good planting mix amended with fertilizer, and adda water-absorbing soil polymer such as Hydrosorb.

Guard against wildfire. In fire-prone areas, create adefensible zone around your house by removing dead vegetation andtrimming back branches that overhang the roof. Clear dead leavesand pine needles from your roof and rain gutters. Store firewoodaway from structures. For more safety tips, go to www.sunset.com and search for”wildfire,” then click on “Wildfire Lessons.”

Reduce transplant shock. Shelter newly set-out plants fromheat and wind for the first few weeks by covering them withfloating row covers or evergreen boughs. To help rootballs retainmoisture, spread a 3- to 4-inch layer of lightweight mulch aroundeach plant. To provide a constant water source for smalltransplants, recycle a 1-gallon plastic milk jug: Poke a hole inone corner with a pin, fill with water, and place the jug where itwill drip slowly over the rootball.