It's hard to believe that the snowflake hydrangea--a glorious plant with huge, 15-inch-wide creamy white, double blooms--is a native and not a hybrid. It can be seen, primarily, in the Southwest in its natural state. However, it can grown in other zone 5 through 9 locations. This perennial can be planted in part shade (morning sun with afternoon shade is best). It blooms in mid-summer to early fall. If you can't find one of these plants at your local nursery or garden center, online plant sites carry them.
Prepare the soil. Dig up the soil in the planting area. Spread 2 inches of compost over it and then work it in the soil with a shovel or pick. Compost amends soils with too much clay and also those with too much sand. It adds needed nutrients to the soil, which will feed the snowflake hydrangea plant. When choosing the planting location, consider the mature size of the snowflake at up to 6 feet tall and a spread of up to 6 feet.
Dig a hole for your new snowflake hydrangea plant. It should be as deep as the current soil of the potted plant and twice as large around.
Remove the snowflake hydrangea from its nursery container. Place one hand around the stalk, close to the potted soil, and turn the plant upside-down, carefully. If the plant does not come out of the pot easily, bang on the bottom of the pot a couple of times. Loosen the roots.
Place the snowflake hydrangea into the hole. Fill in around the outsides with soil, compacting it in. When the plant is stable within the ground, give it a thorough watering. When the ground surface becomes dry, water the plant. Check for watering needs more often during hot spells. This plant prefers to be on the moist side, without being soaking wet.
Fertilize your established (after one year) snowflake hydrangea once in the early spring. Use an all purpose granular fertilizer over the top of the soil under the plant, as specified by the manufacturer's label.