Variegated leaf hydrangeas are cultivars of the hydrangea macrophylla species, also commonly know as hortensia. Known botanically as the cultivar variegata, the shrub produces small lace-cap style flowers in white that will age to pink if the soil is alkaline and to blue if the soil is acidic. The leaves are a mid-tone green and edged in a wide, undulating and irregular border of crisp white. Variegata is hardy in USDA zones 6 through 9, and unlike most hydrangea cultivars, it is grown principally for its unique foliage. Flowering capacity can be maximized by perfecting its cultural conditions with regular maintenance.
Provide a growing location with bright sun or partial daily shade, as complete shade will diminish bloom production. In hot or dry climates, afternoon shade may be preferable to full sun, as it will lessen the stress on the shrub and help prevent wilt or sun scorch.
Water your hydrangea regularly and deeply drenching the soil and root zone to a depth of at least 12 inches. Never allow the soil to dry out beyond the top half inch of soil crust, but do not keep the soil sopping wet either, as this can suffocate the roots. Increase irrigation volume and frequency in the heat of summer and scale back in winter and during rainy springs.
Prune the shrub in the late summer each year after flowering has finished to the desired height and spread. Cut back any weak or unhealthy looking shoots down to the parent branch or trunk. Remove the spent flower heads and stems down to the parent branch or trunk. Leave a majority of the healthy branches in place to flower the following spring and summer.
Fertilize your variegated hydrangea once or twice per year with a complete, fast or slow-release fertilizer with a guaranteed analysis of 5-10-10 or a similar ration of macro-nutirents. Apply according to the product label dosing directions.
Mulch around the base of your shrub with several inches of an organic material each year to feed the soil, hold moisture in and keep competitive weeds from cropping up. Use compost, shredded bark, cocoa bean hulls or similar material.