If you don't have deer, or have a deer fence and you like to water, it's hydrangea time. They're beautiful and worth the trouble, and this year (like most), they're getting better. I'm talking about the blousy mopheads and lacecaps, all of which are very happy with our recent 3 + inches of rain. The Hydrangea macrophylla, as they are technically called, are also known as bigleaf hydrangeas. This big leaf requires hydration, hence the need for soil moisture. The word hydrangea is derived from 2 Greek words: 'hydor' meaning water, and 'angeon', a vessel for storing dry or liquid substances.
Of the many species of hydrangeas, these (in my mind) require a bit more work, although I doubt that many people see it that way because we remember the way they look in June, and July and for the many months after that. With the right light frosting in fall, the foliage can become bronze and red, and certainly the "the cup half full" gardener expects it. We are usually a positive bunch, expectations are high for that perfect frost to bring on perfect fall colors and extend their beauty for yet a couple more months.
So the things that you have to remember with bigleafed hydranges are - they bloom on old wood, you don't want to prune them (unless it's dead wood), deer can't nibble on them and a late frost that kills them back is not good. In other words, anything that damages the old stems will take out potential flowers. Having said that, the positive work in hydrangea breeding is for hydrangeas that bloom on new wood, essentially flowering even if there's winter damage. The first was Hydrangea 'Endless Summer' a winner that was introduced about 9 years ago. There have been many more, one of which is H. 'Twist and Shout', a Michael Dirr introduction with lacecap flowers and a real desire to flower.
A lacecap flower (sort of lacy in its pattern, like a doily) has smaller, fertile flowers in the center surrounded by larger infertile flowers, which are there for show, to attract pollinators and people. The other type of flower is a mophead, all infertile flowers, all flat discs of petals, they will not produce seed.
The second thing you need to know about bigleaf hydrangeas is that you can alter the flower color, up to a point. Your soil pH will determine the color, highly acidic soil will give you bluer flowers, sweet soils will result in pink flowers. Too much, one way or the other can kill them, but the good news is that most nurseries sell small containers of pH adjuster granules that will turn your hydrangea flowers pink or blue and it's safe.
Another recent introduction that flowers on new wood is H. 'Nantucket Blue' a sport from H. 'Nikko Blue', a really good flowering and very popular older cultivar. Essentially you take something that was good and it miraculously got better, or at least a branch of it did and that's how it all started. The flowers are mopheads, full and blousy and lovely.
As these bigleaf hydrangea flowers begin to form, they display a center that is green or white and the color heightens as they open.
There are a few others that I find lovely. Hydrangea 'Oregon Pride' has a full mophead flower with white centers. It's vigirous and dense with reddish stems.
The line of red stemmed hydrangeas goes back to Hydrangea serrata 'Preziosa' with leaves that are slightly smaller but generally reddish in color, even more so in fall. The smaller leaves means it needs a bit less water and it's more cold hardy, loosing less water in winter winds. I still love this old variety and find it very satisfactory.
There is a new bigleaf hydrangea that has been called "mind bending" with it's psychedelic colors. You either love it or hate it and if you do love it, be happy because it's also a new cultivar that will flower on new wood. The petals go from completely green to all pink, striped in a pattern that reminded someone of pistachios.
I'm sort of on the fence about Hydrangea 'Pistachio' and I like different, and I like new. Or so I keep telling myself.
