What’s not to love about hydrangeas? These showy shrubs are the delight of summer blooms. Pink, blue, red and white are some of the colours these beautiful globe shaped flowers are available in.
Type of Hydrangeas
Most Hydrangeas prefer moist, rich soil, and part sun /part shade locations. They generally like a bit of morning sun and cooling shade in the afternoon to perform best and stay healthy.
Bigleaf hydrangea, (Hydrangea macrophylla), a spring bloomer, is perhaps the most widely sought species. They may have either round or flat flower clusters in shades of white, red, pink, blue, purple, and sometimes red. The big round bloomers are called “mopheads” and those with flat blooms are called “lacecaps.”
Hydrangea serrata, or mountain hydrangea, is extremely similar to macrophylla but is smaller and more cold hardy. It is broad with large heads of pink or blue flowers in summer and autumn.
Hardy hydrangea (Hydrangea paniculata) blooms in the summer. The long cone-shaped blooms change in color from light green to white to pink or red as they mature.
The Oakleaf hydrangea (Hydrangea quercifolia) is famous for its large, deep green leaves that persist far into autumn and for its displays of fall shades of orange, red and maroon before dormancy. Oakleaf hydrangea bears its white panicles of blooms in early summer.
Climbing Hydrangeas such as Decumaria barbata and Hydrangea petiolaris are vines which behave politely as they climb walls, fences, and pergolas. Unlike wisteria they are relatively tame and easy to prune.
Wild Hydrangea, (Hydrangea arborescens ‘Annabelle’), is a loose—and wide—branched shrub that likes moist soil or rocky slopes.
Rough-Leaved Hydrangea (Hydrangea aspera) has rough leaves and broad, flat flower heads.
Caring For Your Hydrangea Plants
Hydrangeas are popularly seen in many gardens, grown as shrubs, and now showing a rise in popularity among florists. Here are a few excellent hydrangea plant care tips that can maintain the health and vibrancy of your plant until time to transplant your hydrangeas. Before transplanting your hydrangeas, check hardiness and zone compatibility as these may cause your plant to prefer remaining a houseplant.
Hydrangeas thrive as garden plants and shrubs so house them in areas exposed to full sun or partial shade. However, protect your hydrangea plants from cool, drying winds which could quickly reduce the amount of moisture in the soil.
Hydrangeas absorb water quickly. Keep the soil of hydrangea plants evenly moist and well drained, though this can take watering your plants possibly more than once per day. Hydrangeas grown outdoors as shrubs and garden plants do not need as much attention to watering. However, grow hydrangeas in areas with partial shade and away from drying winds to facilitate moisture retention. Do not keep the sepals (showy part) of hydrangeas moist as this can quickly lead to Botrytis (gray mold) in many species.
Standard potting soil is excellent for hydrangeas. However, the color of hydrangeas is determined by the acidity (pH level) of the soil. A large presence of aluminum ions in the soil produces blue hydrangeas. A soil level of 6.0 and above produces pink hydrangeas. The pH levels of soil do not affect white hydrangeas. Non-alkaline food such as rhododendron fertilizer should be applied once weekly during the growing season to maintain color while providing adequate nutrition.
Hydrangea plants and flowers can be affected by several pests and pathogen (fungal and bacterial) infections. The most common pathogen infection in hydrangeas is Botrytis (gray mold) which is caused by a mild ethylene sensitivity or excessive moisture near the blooms. Powdery mildew, leaf spots, rust and ringspot virus may also affect hydrangeas. Pest problems that hydrangea plants may experience include infestation from slugs and other garden bugs.
PROPOGATION & POTTING
When propagating hydrangeas, root softwood cuttings in early summer or hardwood cuttings in the winter. Root semi hardwood cuttings of non-flowering shoots of evergreens with bottom heat during the summer. In the spring, sow seeds in containers in a cold frame. Pot on your hydrangea houseplants in the late spring or early summer before the growing season. Always allow the plant to adjust to the new soil and container before continuing fertilization and heavy watering treatments.
Fertilizer will not change the color of the blooms. It's possible that extra ingredients added to fertilizers might change the color, but the fertilizer itself doesn't have this power. It is much easier to change a hydrangea from pink to blue than it is from blue to pink. Changing a hydrangea from pink to blue entails adding aluminum to the soil. Changing from blue to pink means subtracting aluminum from the soil or taking it out of reach of the hydrangea. You cannot change the color of white hydrangeas
Hydrangeas are a pruning class IV which includes other deciduous shrubs flowering in mid or late summer to autumn on the previous year’s growth. Hydrangea macrophylla produce new blooms on the current season’s wood. Because of this, damage from cold or incorrect pruning is not as likely to cause a loss of flowers.
Pruning hydrangeas should occur in the early or mid spring, just before the growing season. To prune hydrangea plants, trim off the flower heads that were produced during the last season’s growth. Trim these flower heads to the first bud or bud pair beneath the flower head. For older plants, encourage replacement growth by trimming one-third to one-quarter of older shoots, trimming each to the base of the plant.
Three primary reasons hydrangeas won’t bloom: