Hydrangeas

Types of Hydrangeas
Macrophylla or Big Leaf The macrophylla or big-leaf hydrangeas are the most popular type bearing large mop head bloom in shades of blue/pink or pleasant delicate lace-cap blooms in various shades of white to blue. Many varieties are available with ‘Nikko Blue’ being the favorite. These are the type of hydrangea that change bloom color depending on the PH of your soil (see tips & tricks).

Woodies The “woody” hydrangea consist of tough twiggy shrubs that will bear blooms with a minimum of care. The woodies include the popular Oakleaf, the pink Pee-Gee, the mop-head Annabelle, and the large panicled Tardiva.

Fertilization
At Planting Work some sphagnum peat moss into the soil to improve the consistency of our clay soil. A good quality root stimulator fertilizer for new plantings should be utilized. Water well, then apply a 3-4” layer of mulch.

Established Shrubs should be fertilized in early spring when growth begins with a good tree & shrub food. Do not fertilize again until the bloom buds begin to form. Then fertilize with a high phosphorus fertilizer to encourage large blooms. Always follow the manufacturer’s instructions.

Pruning
If you want to dry your blooms, prune them when the flower is fully developed, but still green or white.

Macrophyllas In late fall, prune your big-leaf hydrangeas to 6-8” and mulch heavily after the first hard frost, usually November (see tips & tricks). Around mid-April, remove the mulch covering the plant and the soil around the plant. Macrophyllas will not begin growth until the soil warms. They bloom on new growth off of old wood. This is why it is vital to protect 6-8” of the shrub from dying back to the ground in winter. Should a late freeze occur after you have removed your mulch, you must re-cover them for protection from freezing. A bushel basket full of leaves works well.

Woodies Prune off all existing blooms, then prune for shape. In spring, thin the plant for larger blooms. Woodies will bloom on new growth.

Tips & Tricks

Our Indiana clay soil is naturally alkaline with a PH of around 7.2. Pink blooms will result from macrophyllas. For blue blooms, add soil sulfer, or aluminum sulfate to acidify the soil to a PH of 6.6 to 6.8.

For red varieties, add some lime, but be careful not to add too much. The PH should never be over 7.4. When flower buds begin to develop, fertilizing with Miracle Grow every 2 weeks for pink blooms or Mir-Acid every 2 weeks for blue blooms will result in huge blooms.

Using a rose collar to protect the old stems of macrophyllas works well. After a hard frost surround the pruned plant with a collar. Fill the collar with potting soil. Water well, add more soil to collar to fill it up. Water again. You are trying to create a dirt ice cube to protect your stems. The inside of an ice cube remains at 32 degrees. The stems of macrophylla will die to the ground at 15 to 20 degrees. Remove the collar and soil from around the plants in mid-April.

Allisonville Nursery
garden center, garden gifts, landscaping
11405 Allisonville Road
Fishers, IN 46038

Phone 317.849.4490
Florist 317.915.8906
Fax 317.849.5948

We are not a mailorder nursery. Plants and products are
available for pick-up at our Fishers, Indiana location.

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