These Hydrangeas have beautiful showy flower heads, varying in color from shades of pink to dark blue. They are also available in white. People often refer to these as 'Mophead' or 'Snowball' hydrangeas
To successfully grow Bigleaf Hydrangeas, you must consider the following:
(1) They demand a regular deep watering schedule. If the soil is too dry and sandy, they will wilt down and not set a nice bud for next year. Hence you will have a yellowish plant with little to no flowers.
(2) They must have shade during the hottest part of the day. If it is too hot and sunny, they will wilt. While wilting every so often will not hurt the plant, every day occurrences of wilting will eventually kill it. Conversely, too much shade inhibits proper blooming. They do need some sun.
(3) They require protection from the harsh winter weather. Usually, the East or South side of a house is an ideal spot. Late freezes in the spring will kill new buds that would have otherwise produced flowers. Harsh winds could kill off entire stems. Although the plant would come back from the root zone, the top die-back would destroy any potential flowering for that year.
(4) They MUST NOT BE TRIMMED unless absolutely necessary. Purchase a hydrangea to fit the spot. If you find that it gets too big, move it or prune very lightly. Those sticks you have to endure all winter are going to produce the flowers. If you remove these sticks, you remove the flowers. If you have a great need for a tidy look, don't plant Bigleaf Hydrangeas!
Following are some helpful tips to produce successful hydrangeas: ******************************************************************************** If you have sandy soil, embellish it with lots of peat and top soil. Soaker hoses and water timers are highly recommended to ensure proper watering.
If the area in which you planted gets too much winter exposure, mulch deeply with leaves, woodchips, pine needles, etc...cover the plant! Then remove the mulch as soon as the hard freezes are done in the spring.
Want to turn pink hydrangeas blue? You can do this easily by creating an acidic environment. First, test the pH of your soil. pH tests are cheap and easy to use. If your soil is neutral to basic (7-14), your hydrangeas will be pink. If your soil is acidic (1-6.8) your hydrangeas will be blue. Add acid in the form of Peat amendments, Miracid, Iron sulfate, or Hollytone. To keep things pink, add lime in the form of dolomitic limestone. Check your pH regularly to ensure that you don't go too far in either direction.
Another good way to change pinks to blues is by adding Aluminum sulfate. This directly adds Aluminum to the soil for immediate take-up. Aluminum ions are responsible for the blue-color. Essentially, by making the soil acidic, you are making Aluminum more available to the plant. However, if your hydrangeas are planted near other plants that may not appreciate aluminum sulfate, the other methods are better.
There are some varieties of Bigleaf hydrangeas that will never turn blue. These are forever pinks. But most will change. There are also some white varieties available. White will always be white. Some will fade to pink with age, but they will always start out white.
If you want to avoid all this detail and you are happy with white or pink, plant the PG Hydrangeas! Hydrangea paniculata grandiflora is a wonderful family of hydrangeas that you will recognize quickly. They have large cone shaped, often loosely arranged flower heads. They tend to get very large, ranging from 5 feet up to 15 feet. The great news about PGs is that they can be trimmed, planted in a fair amount of sun, and fairly ignored for most of their existence!
PG Hydrangeas are strongly recommended for the lakeshore and Chicago areas because of their extensive hardiness. They bloom on new wood so it doesn't matter if they die back to the ground. Think of them like big tough perennials!