It has been a while since I wrote about a plant, the last one was the North Star Sour Cherry. That was a plant I had at my previous house and was quite familiar with. It is also a pretty old cultivar, certainly not the latest and greatest. Today, I want to talk to you about a new cultivar of an old friend, the Haas Halo hydrangea.
Most people know the Illinois native Smooth Hydrangea because of the softball sized mophead white flowers of it’s most widely planted cultivar, the Annabelle Hyrangea (Hydrangea arborescens ‘Annabelle’).
While these are attractive plants from a landscaping sense, the flowers are sterile and not much use for pollinators like butterflies or bees.

You see those white mophead flowers are all made up of sterile flower parts. I have wondered, why can’t we find the good old species of Smooth Hydrangea. You know the one with the sterile AND less gaudy fertile flowers that contain pollen. Then of course, I remember that the flower is pretty unspectacular compared to Annabelle.
Those plants don’t look nearly as ornamental as an Annabelle, but they do fit into natural landscape design as a supporting player and have more ecological benefit to wildlife. That is they would if you could find a nursery that sold them.
Why couldn’t we have an improved Smooth Hydrangea WITH fertile flower parts that support pollinators?
It turns out, now we can!
Haas Halo Hydrangea
(Hydrangea Arborescens ‘HAAS’ HALO’ PP24783)
Introducing Haas Halo Hydrangea, finally an attractive hydrangea that no longer just looks pretty but pull’s it’s own ecological weight. This is THE shrub I am most excited to get out and start using next year!

Here is the reason
Here is a close up of an Annabelle Hydrangea flower.

By contrast, here is a close up of a Haas Halo Hydrangea flower:

So besides looks, what’s the difference?

Those fertile flowers offer nectar and pollen to a wide range of visiting pollinators. These visitors include bumblebees, little carpenter bees, Halictid bees, masked bees, among others native bees that need all the help we can give them.
The foliage of Wild Hydrangea is also nibbled on a bit by the caterpillar of the Hydrangea Sphinx moth which turn into this kind of pretty moth (and tasty piece of bird food).
Besides it’s vastly superior ecological benefits, Haas Halo Hydrangea also have the advantage of being drought tolerant, which for a Smooth Hydrangea is a great benefit as they can be a bit thirsty.
Haas Halo Hydrangea Growing Conditions
- Hardiness Zones: 3-9
- Bloom Time: June to October
- Size: 3 -5’ tall by 3 – 5’ wide
- Sun Requirements: Full sun to partial shade.
- Soil Moisture: Moist to dry.
- Diseases: None known.
Haas Halo hydrangea contributes to ecological landscape plantings, but can also be used in foundation plantings, cutting gardens, mixed borders, and of course, native plant gardens.

Of course, you won’t find many landscapers using this plant. Most are not concerned about building ecological plantings that support biodiversity AND look great. Well at least 95% of them.
They are more concerned with using the old tried and true proven plants that they know they won’t have to replace. That’s why you still see Bradford Pears, Burning bush, and Daylily still planted everywhere.
Stay tuned to my next post, where I will share a design for an ecological landscape that uses this plant (and a lot of other ones).
It’s mid-October 2022. I would LOVE to buy this plant for a fall planting but can’t find any place – local nursery or online – that sells it. Does anyone know where I can purchase this?
I love this Hydrangea. I purchased 2 last year locally and this year they are growing so fast and have a lot of buds on them. The flowers last a very long time and they are beautiful. I couldn’t be happier.
I have a woodland shade garden in western Massachusetts where parts get 2-3 hours of morning sun a day. Will Haas Halo work in it?
It might. I would expect it to grow but it might not flower as much.
I have this and it is spectacular. I enjoyed reading your comments.
What part of the country are you in? I am in zone 9 and I wonder just how truthful the “zone 3 to 9” category is.
Zone 5.I would not trust it in zone 9.
I forgot to cut back my Haas Halo earlier in spring and now it is startling to leaf out. Is it too late to do it this year?
Thank you!
I would leave it, but you could reduce it a little bit.
Where can I buy these plants? I live in Aurora, IL. Do you sell these in McHenry at Anderson Natural Landscapes?
No. I don’t sell or plant them yet as I have not found a supplier. I heard Northwind Perennial Farm in WI had them this summer. I would call around and ask for them as most places stock is low. I always liked the garden center at Schaefer Greenhouses in Montgomery, I would give them a try.
Hi—I bought 2 of these 2 yrs. ago and planted them in my mixed border—I LOVE ’em! Took 2 yrs. for them to really get size and bloom, but they’re a knockout in a mixed border, and would look good as a foundation specimen, as well.
Nice. Thanks for the feedback..
Hi Jim,
I believe I have a Haas Halo that I bought from ColdWaterPond Nursery in Phelps, NY. It is mislabed as Annabelle, and I’ve always wondered why the flowers are so less showy. Now I know why and can appreciate them more. My question for you is – hardly any of the petals on mine open. They are all the small un-opened flowers that your white arrow points to, above. Is there a way to get more of those to open? I can send a photo if that helps? I was going to pull it out this fall and get an Annabelle, but now maybe I will not. Thanks for writing this and making me appreciate what I have.
It is probably the straight species. The blooms may improve if it gets more sun, but don’t expect is to compete with an Annabelle or Haas Halo.
I just found Haas Halo at Northwind Nursery north of Lake Geneva, Wisconsin.
What about H. arborescens “White Dome”? I can’t find Haas Halo in my area (Chicago), but one nursery has White Dome. The Missouri Botanical Garden suggests that it produces fertile flowers:
http://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?kempercode=c699
Do ya cut it back in spring like Annabelle?
Yes, prune it the same as Annabelle.
Cause I haven’t really found that the straight species arborescens respond to cutting back hard as well as the Annabelle does
I would not cut any of them back real hard.
Yes, you can get away with cutting Annabelle back almost to the ground but it will weaken the shrub. I would prefer light pruning annually.
Would anyone know why my mop head blooms have changed to the halos? Over the past 3 years, each year a new shrub has blooming with the halo instead. Although they are beautiful, I miss my mop head blooms! Help me!
Very curious about this plant. Thanks for the post.