Updated – June22, 2021
If you love hydrangeas, you know that some are challenging to grow. But, these are only the macrophylla hydrangeas. There are MANY more hydrangeas out there for Ohio gardens – even in reds and pinks – without the hard work and frustrations.
Learn about all of the different types of hydrangeas and the cultivars best suited for Ohio gardens through the presentation in the link below:
Hydrangeas 101 – 2021 – Handout
More copies of the Hydrangeas for Ohio Chart can be printed at: http://go.osu.edu/hydrangeas
I have an ‘Endless Summer’ hydrangea. In recent years it has produced a lot of foliage but few flowers. This year I am taking extra care to keep lawn fertilizer away from the hydrangea to avoid exposure to nitrogen, which I think of as primarily a feeder of foliage. I have seen the recommendation to use an all-purpose soluble fertilizer like Miracle Gro on this type of hydrangea — but with an analysis of 24-8-16 might that be too much nitrogen, again promoting too much foliage growth? (I don’t care whether they are pink or blue, I’d just like a few more blooms.)
Hi –
I’m assuming you purchased an Endless Summer, and not another type of hydrangea. I only note this because many gardeners make an assumption that all mcrophylla hydrangeas are Endless Summer because of the popularity of this brand. Most of the time, our blooming issues relate to other types of macrophylla hydrangea that bloom on old wood only. These plants bloom only every couple of years in Ohio. For ones that bloom on old wood, winter protection is a must. For Endless Summer, we should not be having this issue, as they continue to set blooms throughout the growing season. On my own plants, I seed buds at the end of May, around the 4th of July and a third set around Labor Day.
Second, I’m assuming you have done a soil test and have the necessary pH range and nutrient values for hydrangeas. Ensuring the soil is well drained, has the correct nutrients and pH are all prerequisites for growing a healthy plant. For example, excess phosophus affects beneficial microorganisms in the soil, causing a plant to focus on root growth in expense of other plant functions – see https://ag.umass.edu/cafe/fact-sheets/fertilizing-flower-gardens-avoid-too-much-phosphorus
While the value of a general, all purpose fertilizer may have a higher N level – these plants do need it. Note the thick, green foliage of a macrophylla hydrangea.
Like other flowering/fruiting plants, too much nitrogen early in the growing season does indeed an effect that promotes vegetative growth, slowing the process to reproductive growth (flowers). Thus, nitrogen early in the growing season has the most affect on flowers. You can try a different water soluble fertilizer that has a lower N level. Many types should be available at your local garden center.
So, if you haven’t – do a soil test. Adjust soil based on the test.
Continue to shield the plant from N applications to the lawn (considering moving it).
Limit fertilization based on your soil test until you begin to get blooms.
Protect the plant this winter – count up three buds, cover with a bag of mulch. If you get blooms next spring from that ‘old wood’ – then the plant you have just blooms on old wood and not new wood. See other instructions on winter protection in the powerpoint.