Many so-called reblooming hydrangeas have this issue - little to no flowering from the current season's growth. Why this happens is a bit of a mystery but it just seems to be a common theme with new wood bloomers. Maybe those reblooming genes just do not have sufficient time to develop flowers on that newly produced growth......?

IMO, the only sure way of obtaining good flower production on these plants is to provide winter protection just as you would do for the old wood bloomers. The less exposure to cold they have, the greater the chances that you will see any flowering.

Thanks for the reply. Aside from burying them in mulch, is there anything else you recommend for winter protection? They are in an area that gets morning sun, but afternoon shade, so it isn't exactly a warm winter spot, but if I move them to an area that gets more winter sun, I'd be scared they'll get too much sun in the summer.

First news. Well, I have never thought of Big Daddy as a rebloomer here. There was a big planting done recently here in a city garden with about 12-14 BDs but I never observed them reblooming after the first Spring flush. So, knowing that even remontant ones have blooming issues in some locations like yours (zones 4-6), I would recommend either winter protecting them with organic mulch until after your average date of last frost or switching to a cultivar of hydrangea arborescens or hydrangea paniculata that you may like.

Paler leaves might indicate that the soil is getting too alkaline, the foliage is too new or is not getting enough sun (after coming out of the winter protection, for example). Hydrangeas are normally not grafted in the US but I have heard of some people saying they have grafted hydrangea paniculatas in Canada. Dappled sun or early morning sun only until 10am or so should be fine.

In colder climates for macs - anything below zone 7 - the best winter protection methods are a bit more complicated than just a thick mulch. Caging the entire unpruned plant and then filling that cage with leaves, straw, etc. is the usual method but you can review previous posts on the subject for other ideas: https://www.gardenweb.com/discussions/hydra/query/winter-protection/nqrw

And even in parts of zone 7 (and higher), winter protection may be advised if that location is subject to early spring frosts/freezes, which can actually do more damage to flowering potential than all winter long cold.

PS - See how much sun the area gets this summer (August?). Make a note in a wall calendar reminding you to check or set up an electronic reminder.

In order to bloom from new wood, the stems need to be able to get ol and tall enough. Lack of enough sun may cause slower growth. Some composted manure may help during the start of the growing season.

The link above does not "look" right.

My experience with rebloomers is the bloom is around Sept/Oct for me. Doesn't get enjoyed that much as the blooms are smaller and things start to wind down in the garden anyhow

luis, curious as to how that link doesn't look right. When I click on the link, it takes me to the search page for winter protection in the Hydrangea forum. What does it show you?

(Doesn't work right for me either. It just takes me to the main Hydrangea page.) There is some redirect. It changes the url to https://www.houzz.com/discussions/hydrangeas

Well, that's interesting. I am only accessing the site via GardenWeb, never Houzz. I wonder if that makes a difference? And only with a laptop, as the phone app is useless.

The URL name does not "look" like the one for this post. I tried it and it redirected me to the list of posts in the hydrangea forum... same as cvw_ky indicated.

Hmmm...... Maybe just the difference being GW focused rather than Houzz. I have no other explanation :-) It works perfectly well for me.

But you can always do a forum search yourself. Just make sure you are in the Hydrangea forum and type in "winter protection" to the search bar and you should be directed to the same listing of discussions under that topic heading as my link was intended to do!

The Gardenweb/houzz connection must be some of the issue. When I did the search, my url looks like this: https://www.houzz.com/discussions/hydrangeas/query/%22winter-protection%22/nqrw

Anyway. Sounds like maybe there is evidence that my Big Daddys aren't getting enough sun? The small pale leaves, slow growth, old-growth dieback, etc. I'm going to try moving one further out into the sun and see if that helps. Then my next dilemma will be what to put in that shadier spot.

Thanks for all the replies!

All my hydrangeas are grown in pretty much all day shade. If they get any direct sun, it is at most only an hour or two but direct sun in my wooded shady garden is a rare commodity :-) Pale leaves could be an indication of excessive shade but it's not something I've ever seen - my leaves are a uniformly deep and lush dark green. I'd attribute the paleness to more of a possible nutrient issue than to shade. Slow growth or old growth dieback have no association with shade. They are far more likely to be climate related.

Thanks gardengal.

In looking back through my pics of the plants, I am also noticing some dark green veining in addition to the pale leaves. See below. The July pic doesn't look half bad, although the leaves are large and deep green like they should be. By september the leaves look washed out.

July

September

Normally, with iron chlorosis, the leaves turn light green at first. Then they turn yellow-ish, except for the veins which remain dark green. If the soil acidity is not corrected, the leaves can turn a little white-ish but the leaf veins remain dark green. There are formal soil tests that you can request to ck the soil pH and check for nutrient problems. Or you can buy test kits from plant nurseries... Though they may not have adequate stock in some places in early March.

I live in Indianapolis and have tried lots of things to protect macrophyllas during the winter..the most successful method was growing in a pot..then overwintering the pot in my shed..but it's tricky when you bring it out in the spring..you need to move it in and out often to avoid spring freezes..heavy mulch wouldn't protect the buds..I decided that macrophyllas aren't worth the trouble in my zone..there's lots of posts about this topic because macrophyllas in colder climates are a problem for everyone..try arborescens, paniculatas and oakleafs..still pretty and effortless compared to macrophyllas..some arborescens and a Bloomstruck in a pot..

And on a related note...Do I need to thin some of these out?

I like to prune crossing branches all the way down. You may also want to consider doing the same to stems that are growing way too much compared to others or consider partially pruning them instead. The ones that are growing flat down can be put on a watch list and see if they do not self correct once the sap is moving actively. But otherwise, it does not look that bad. If I did not have time for the task this year, I would not mind waiting to prune it another year. Hope you have lots of blooms.

I tie the branches of my macs together and put them in round chicken wire cages stuffed with mulched leaves. I make sure that the branches are completely surrounded by a heavy pile of leaves in both the center of the plant and the outer part of the plant between the plant and the inside of the cage. I also put a layer of plastic on just the top of the leaves (open at the sides) to keep some of the moisture out of the center of the leaves.

Hey all. Popping in here to give an update and ask another related question.

First, an update. Based on gardengal's suggestion, I got a soil test and found the ph level is 7.8, which I have learned is very high for hydrangea health. I purchased some soil acidifier and applied it to both plants, along with some iron tone and some peat moss. This was done in 2 months ago.

Today, I went out to give everything a closer look, as well as prune out the dead stems. I have mostly new growth coming straight from the crown, which means most of the shrub died all the way back. However, I have a couple of stems that survived and are sprouting leaves. I also have one or two monster stems, the size of which I have not gotten before. Usually the stems are little whispy fellas about the size of a pencil, or maybe your pinkie. These big ones are about the size of your thumb. Also, the leaves are as large as I have seen them, at least in a while. They aren't as big as they need to be, but at least they aren't the little runts I have been getting.

However, I noticed some of the leaves started to show signs of chlorosis again. See the pics below. Is it too soon (2 months later) to see a results from my soil acidifier/irontone application, or should I apply more, or apply something else?

Big Daddy rarely blooms for me here in Tidewater Virginia when everything else does.

So what is the pH now, cvw_ky? Do you know? Is it time to re-apply per label directions? Just wondering how much of a pH change has happened after applying these three different products.

A single application of a product may not bring down the soil pH down enough so one needs to continue reapplying forever and see gradual improvements. I would suggest getting a pH meter with numeric results so you can also test on your own and monitor the pH. Apply per the product instructions for a while and then tweak it higher -slowly- if the pH stabilizes and does not continue going down. But be careful to follow instructions and not use too many products because sulfur containing products can burn the tiny, shallow hydrangea roots. I typically just use one product at a time. I would read the instructions for your products to see what warnings they have about applying them early if after 2 months is too early; fyi: my old bag of Iron-tone says it is 17% sulfur.

Note that there are times when it rains too much and I observe leaves doing this but, they do it temporarily. After the rains stop & the soil dries out/drains the water then the dark green color returns.

Thanks luis_pr. We have had a lot of rain recently. Like...a lot. Maybe that is our issue. I will be patient and see if things improve. If they don't, I will look into a pH meter and then where to go from there.