DON'T PRUNE TO FIT
Trying to make it a smaller plant to fit the space won't work. Instead look for a plant to fit your space. There are many varieties that will stay smaller in comparison to their full sized counterparts. Some of our favorites are 'Mini Penny', 'Little Lime', 'Pia', and if you are looking for an oakleaf hydrangea check out 'Pee Wee'. Just remember pruning is not the same thing as deadheading (removing old blooms).
OLD WOOD vs. NEW WOOD
It is important to know whether your hydrangeas bloom on old wood (existing stems) or new wood (new spring growth).
OLD WOOD
For a visual aid on pruning Mop Head and Lace Cap hydrangeas, click here. This is a resource provided by the website, gardenlady.com. You will find a good line drawing with straightforward information. Remember that pruning after July will most likel take off some flower buds. Another reason not to prune late is the potential for a delay in dormancy; new growth forced could be hit by frost and really make the plant ugly or even possibly kill it.
NEW WOOD
This is the most straightforward group. It includes H. arborescens ("Annabelle") and other favorite varieties such as "Limelight," "Little Lamb," and more. They may be cut back if needed immediately after flowering and may rebloom if there's enough summer left and the plant has adequate food (Hollytone). When "Annabelle" blooms, cut 12" of stem to best display the beauty in a vase and it will rebloom to your delight without the flop due to the stronger stems. The second bloom will be slightly smaller flowers but still very worth doing.
• Method 1: cut ALL stems at ground level. This will produce a large number of flowers but they may flop over because the stems aren't as sturdy and the flower heads are heavy.
• Method 2: Cut the stems to a height of 18" to 24" above ground level to provide a sturdy framework to support the new growth. This framework will help control the tendency to flop.
A tidbit of trivia on the "Annabelle" hydrangea: Many thanks to
the two belles, Harriet and Amy Kirkpatrick from the community of Anna in Union
County. Harriet spotted it while horseback riding back in 1910. With her sister
Amy, they returned the next day and dug it up. Bam! We have "Annabelle" thanks
to those two belles.
This season we also
have the "Invinciball" hydrangea which has a much larger white flower when compared
to "Annabelle." We should also see the brand new "Bella Rose" Hydrangea; a
strong pink "Annabelle" with strong stems.
EVERBLOOMING HYDRANGEAS
This is a growing list of repeat flowering shrubs both mop heads and lace caps. Their growth habit is to bloom, rest, and then repeat another bloom in the same season. Some of the named varieties are "Penny Mac," "Mini Penny," Twist N Shout," and "Blushing Bride." They all enjoy morning sun, moist, organic soil that will have soil moist reserve capacity. The soil needs to feel almost like a damp sponge. The really nice thing about this group is that no matter how you whack them they can still bloom. The color of the flower on some of these will depend on your soil pH. Please remember that if your plant already has flower buds on it you will not be able to change the color at that time. You get what you get!
This is a growing list of repeat flowering shrubs both mop heads and lace caps. Their growth habit is to bloom, rest, and then repeat another bloom in the same season. Some of the named varieties are "Penny Mac," "Mini Penny," Twist N Shout," and "Blushing Bride." They all enjoy morning sun, moist, organic soil that will have soil moist reserve capacity. The soil needs to feel almost like a damp sponge. The really nice thing about this group is that no matter how you whack them they can still bloom. The color of the flower on some of these will depend on your soil pH. Please remember that if your plant already has flower buds on it you will not be able to change the color at that time. You get what you get!
SOIL pH
The very best way is to test soil at the Ellington Agriculture Center (615) 832-5850. They need about two handfuls in a baggie. Take the sample from about 12-15” deep, where the roots would be found. Ask for the basic soil test for the acid loving trees and shrubs recommendations, to get the best blue color in the flower. They will tell you how much sulfur to use per 10 sq. ft. to get a pH number of 5.5-5.7. The way this dab of chemistry works is that the acidic soil dissolves aluminum, and it’s this aluminum that will make the flower blue. We are not fans of aluminum sulphate! At high levels it’s toxic to the plant! And with a heavy handful you can get the cremation effect. For pink, it’s so simple, our soil is derived from limestone rock and at best it will be weakly acid to neutral. Aluminum does not dissolve, thus the flower will be pink.
The very best way is to test soil at the Ellington Agriculture Center (615) 832-5850. They need about two handfuls in a baggie. Take the sample from about 12-15” deep, where the roots would be found. Ask for the basic soil test for the acid loving trees and shrubs recommendations, to get the best blue color in the flower. They will tell you how much sulfur to use per 10 sq. ft. to get a pH number of 5.5-5.7. The way this dab of chemistry works is that the acidic soil dissolves aluminum, and it’s this aluminum that will make the flower blue. We are not fans of aluminum sulphate! At high levels it’s toxic to the plant! And with a heavy handful you can get the cremation effect. For pink, it’s so simple, our soil is derived from limestone rock and at best it will be weakly acid to neutral. Aluminum does not dissolve, thus the flower will be pink.
ADDITIONAL TIP ON HYDRANGEAS
Once in a while you will encounter a reason to skip a season of bloom. One of our horticulturists notes the following, "I did this when I first planted a very young ‘Limelight’. First I pruned it to develop its structure. Next, I used Hollytone fertilizer as a little extra food. This brand is all organic, and non-burning and contains very low soluble salts. Under normal conditions, it last 60 to 90 days. Next, I did NOT allow flower buds to develop. In effect, this will direct energy to the root system. Remember that flowering is an energy draining process by the plant. This will help redistribute energy to other neglected areas to help overcome stress from drought or insect damage."
Once in a while you will encounter a reason to skip a season of bloom. One of our horticulturists notes the following, "I did this when I first planted a very young ‘Limelight’. First I pruned it to develop its structure. Next, I used Hollytone fertilizer as a little extra food. This brand is all organic, and non-burning and contains very low soluble salts. Under normal conditions, it last 60 to 90 days. Next, I did NOT allow flower buds to develop. In effect, this will direct energy to the root system. Remember that flowering is an energy draining process by the plant. This will help redistribute energy to other neglected areas to help overcome stress from drought or insect damage."
