Hydrangea help

Asked June 17, 2020, 6:18 PM EDT

Hi, I bought a property with 4-5 hydrangia bushes. When we moved in, they had beautiful blooms. Not knowing how to care for them, I did not do anything and most of the foliage never came back. This year, I added soil acidifier and granular fertilizer for acid loving plants, and the foliage is looking much better. My question is about pruning. I pruned off all of the dead stalks about 2 weeks ago, before which the plants looked terrible. In the fall season I left 1 of the plants alone, 1 I pruned all the way to the ground and the others I did something in the middle, pruning what I thought was dead. The foliage of the plant I pruned all the way down is the best of all of them right now, however I noticed on the plant I didn't prune at all, there are live branches coming off stalks that look dead. There are no blooms I can see on any of the plants. Which way should these be pruned? Unfortunately I do not have any pictures from the first year when they were blooming, but I have pictures from just after I took out all of the dead tissue

Baltimore County Maryland

3 Responses

Hydrangeas are beautiful, aren't they?
There are several types, and yours looks like what is termed a Big Leaf Hydrangea (H.macrophylla).
First know: that early first year when you did nothing and they didn't come back was likely no fault of yours. In our area when we have an unusually cold winter, the plants can be killed back to the ground (roots ok) or less often completely lost.
Most of these types of hydrangea bloom on wood made the previous season, so if the live stems are killed, or the pruning is done at the wrong time, the buds/blooms are lost as well.
There are newer varieties that are supposed to bloom on both old and new wood so winter kill and incorrect timing of pruning is less of a problem.
For most Big Leaf though, wait until spring to see what stems are still alive. The ones that are brittle and dead, prune out (you can scrape the wood with a fingernail to see if it is brown (dead) or green(live) underneath).
This late, you can see in your first photo that most of them are dead and you can just prune them back.
Leave the ones however that have some leaves still showing on the stem. These are the older, live branches that you are most likely to get flowers on this year.
It is not uncommon to have a late frost nip some buds just coming out of dormancy in our area.

Clear as mud, right?? This page might help clarify things better than I just did:
https://extension.umd.edu/hgic/topics/guide-pruning-hydrangeas

Good luck and let us know if we can help further.


Christine

Hi, I haven't really done anything to the hydrangeas besides pruning the dead stalks back in June. It seems like most of the foliage has died and fallen off and 3 of them look pretty terrible. The photo of the leaf with leaf spot is on the one plant that still has most of the leaves as was healthiest overall. What should I do to make sure there plants don't die over the winter? What do I do to prevent this next year?

Hydrangeas often have dead stalks in spring that got killed with cold weather.

If your hydrangea is dying over the summer, they need to be
1. watered more (if they wilted, that's a sure sign that they needed water). We see iris in the photos. Iris like is hot and dry, so if they are happy in that locations, that suggests too-dry soil.
It's also possible the hydrangeas are getting
2. too much water (we've had a lot of rain late summer until now). Hydrangeas like moist soil--not sodden, soggy soil that doesn't drain well, or sitting in standing water.

The fungal leaf spot disease is common and not killing the hydrangeas.

You may want to replant with shrubs that like hot dry conditions, such as junipers.

Ellen

Do not prune off green stalks in late summer, fall, winter or spring! They need green stalks from the summer before in order to bloom. You can only prune green stalks immediately after they bloom.

Dead stalks can be pruned anytime. (Of course, it looks best to do this in spring.)