Camellias, azaleas, dogwoods, deciduous magnolias, lilacs and other spring-blooming perennial plants and trees should be pruned soon after they’ve finished flowering. Azaleas and camellias set the buds for the next season’s bloom in late spring and if pruned or sheared at any other time during the year, the pruning will remove next year’s flowers. Prune azaleas by cutting long, wayward branches back to a junction or to the main trunk; trim camellias to maintain size by cutting vigorous top and side branches back to a junction.
The colorful bracts that surround the actual flowers on dogwoods form in fall (and so can be damaged by hard freezes); dogwoods and and deciduous magnolias are pruned after flowering, but before the new leaves appear.
Most older lilac species set flowers on last year’s wood. Prune lilacs by cutting off spent flowers back to a double-leaf node and encourage the growth of new wood by cutting a few of the oldest branches down to the ground each year.
Dogwoods and deciduous magnolias as well as forsythia, hawthorne and viburnum need little fertilization, except to correct serious nutritional deficiencies. Azaleas and camellias do need regular monthly fertilization during the summer months. They are acid-loving plants that do best when the soil pH is below neutral or around 6 or 6.5. Our soil and water are highly alkaline, with pH levels well above neutral. The burned leaf tips and edges we often see on camellias and azaleas are caused by high alkaline or high salts levels. High salts levels cause deficiencies in major nutrients, especially iron, which show up as leaf yellowing or blotching.
Shade plant fertilizer formulations should contain extra sulfur, at least 5 percent. Sulfur helps lower pH levels so that root systems can more easily draw up important nutrients. A half cup of sulfur granules added to a cup per bush of a regular flower and vegetable fertilizer will have the same effect. Flushing the soil with water to force out excess salts can also reduce pH levels. Flush the soil around all shade-loving plants several times a year.
Camellias and azaleas are remarkably drought tolerant when well-established in well-amended soil. Replace mulches around them regularly with a shade plant compost or humus-based planting mix that can be worked into the soil. Remove all fallen camellia flowers and petals before replacing mulches to prevent the spread of camellia blight fungus spores, then top the existing mulch with another 3- to 4-inch layer.
Note: The Clovis Botanical Garden, 945 N. Clovis Ave., is having its annual fundraiser 5 to 7:30 p.m. Thursday, May 12. This year’s theme is “Around the World in 80 Bites.” Tasty snacks and beverages from around the world will be offered in each area of the garden and there will be music, entertainment and a raffle. Tickets are $45, $40 for members. For more information check the garden’s website, www.clovisbotanicalgarden.org.
Send Elinor Teague plant questions at firstname.lastname@example.org or email@example.com (“plants” in the subject line).