How to Care for a New Outside Hydrangea
- 1). Spray water onto the leaves and into the soil surrounding the new hydrangea until the plant and soil are moist. Do not allow the water to pool around the hydrangea. Overwatering will cause the roots to rot. Water the hydrangea daily, keeping the soil constantly moist.
- 2). Mix compost with mulch and spread an even, 2-inch thick layer of the mixture around the bush soon after you plant it outdoors. Do not allow the mixture to contact the stump of the bush because the compost can burn the bush. In general, mix one part of compost for every two to three parts of mulch. Use higher concentrations of compost in nutrient lacking soil, and less compost in soil that is high in nutrients.
- 3). Spread slow-release fertilizer around the bush in mid-summer and cover the fertilizer granules with mulch. Do not fertilize or spread compost around the plant after August because the addition of nutrients during this time interrupts the plant's preparations for winter dormancy.
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