Hydrangeas are between the most well known flowering shrubs in Mississippi and across the region.
But when conversing to property gardeners, it appears these wonderful shrubs are shrouded in secret about how to care for them in the landscape. Whether or not it’s pruning, modifying flower colour, feeding or watering, dwelling gardeners want the correct info to help them be profitable hydrangea growers.
The No. 1 hydrangea query I get in the spring is, “When do I prune my hydrangeas?” My very first reaction is that the respond to depends on when the hydrangea flowers bloom.
The bigleaf hydrangea and oakleaf hydrangea, recognised botanically as Hydrangea macrophylla and Hydrangea quercifolia, respectively, usually set flower buds on previous wood from the earlier year, like azaleas. If you prune these crops early, you clear away all those flower buds. That indicates you prune bigleaf and oakleaf hydrangea later on in the spring after they flower.
A newer huge leaf hydrangea introduction is Limitless Summer months, which can bloom all over the calendar year on equally outdated and new wood.
Hydrangea these as the the panicle, or Hydrangea paniculate, and the common Annabelle, which is Hydrangea arborescens, bloom in the late spring and through the summer time on the current season’s growth. These shrubs can be pruned in early spring just before the shrubs leaf out. If you want, you can slender out the stems and prune down the branches by no more than a person-third.
The other main question I get concerns how to alter the coloration of hydrangea bouquets. This is challenging and involves a minimal little bit of soil pH chemistry.
The initial thing to understand is that this does not do the job on all hydrangeas. Only bigleaf hydrangeas can reply to changes in soil pH, so don’t even attempt it on the other species.
A soil pH of 6.5 and previously mentioned final results in pink flowers, and, usually, there is not a problem rising flowers of this coloration. It receives difficult when you try out for blue bouquets, as the soil pH wants to be 5.5 or down below.
Adding iron to the soil can lower pH an aged recommendation was to bury a can of rusty nails less than the hydrangea. This is not a good thought for the reason that lowering the soil pH is only aspect of the tale. Aluminum is also necessary to generate blue bouquets.
Incorporating aluminum sulfate can fulfill both equally requirements, but it normally takes time and ought to be recurring as the soil will normally revert back again to its natural pH.
One more bit of suggestions about striving to modify soil pH for a individual hydrangea flower coloration is to get a soil examination finished initially. It will guideline you moving ahead. It is common for bigleaf hydrangeas to generate purple bouquets for the reason that the pH was neither much too small nor way too high. I like to get in touch with these “blurple” bouquets.
A much better solution is to plant bigleaf hydrangeas that have been bred to be either blue, white or pink. These shrubs do not respond to soil pH modification and screen vivid, very clear hues every single yr.
All of the independent back garden centers I’ve visited over the past six months have had lovely hydrangeas just ready to go dwelling with you.
Gary Bachman is an Extension and study professor of horticulture at the Mississippi State University Coastal Research and Extension Center in Biloxi. Get in touch with him at [email protected]