Answer: If you have the standard garden variety of Hydrangea, plant it now and leave it in the ground all year 'round. Plant in a partially shady spot, with at least some protection from hot afternoon sunshine. Prepare the planting hole by digging one slightly larger than the pot your plant is in. Loosen the soil, then lay the pot on its side and gently remove the plant. You may have to tap the sides and bottom of the pot to coax the plant out. If the roots are spiraling around, straighten them out so they'll grow out instead of around in a circle. Plant at the same level it was growing in the pot and firm the soil all around the roots. Then water well to exclude any air pockets around the roots.
Hydrangeas produce blossoms on new shoots that grow from the previous year's wood. If you prune carefully after the blooms are spent, taking one-third to one-half of the old wood, new flowering shoots will appear the following spring. Plant in rich, porous soil (amend with compost or peat moss to retain just the right amount of moisture), and mulch the root zone to help suppress weeds. Hydrangeas are fast growing shrubs. Prune the flowering
stems back to the ground each year to make room for new stems that will produce flowers.
You can change the color of hydrangea blooms with a simple soil treatment. Pink and red bydrangeas often turn
blue or purple in acid soils, and plants can be made red by liming the soil or applying superphosphate. For blue flowers, treat the soil with 2 Tablespoons of aluminum sulphate per plant, making 4-6 applications at 2 week intervals, starting in the early spring before the plants bloom. (Sulfur will acidify the soil. The desired pH range would be between 5.5 and 6.) For pink flowers, add lime to the soil, to raise the pH above 7.8). Test your soil to measure the pH range.
Hope this tells you everything you ever wanted to know about hydrangea's!
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