What's Happening Here?

I recently visited a grower in Illinois and found something all too familiar when walking the greenhouses and taking in all the beautiful perennials they were growing.

Growing plants can be a very rewarding experience, however, producing plants can also be very humbling. Often times, just when you think you can see the finish line and feel pretty good about a crop, something happens, your bubble is burst and suddenly your ego is brought back to reality.

What I observed that day reminds me of one of those moments I experienced when I was a perennial grower. Check it out:

Look at the peculiar patterns on this rudbeckia. If I use my imagination, I see a leaf-like pattern in the center of the leaf. Maybe it’s just what I see (don’t get me started with all the wonderful things I see when looking up at the clouds in the sky).

I guess I should come back down to earth or at least to ground level and continue with this diagnostic challenge. Have you seen this or other similar patterns on rudbeckia before? Look again and focus on the colors of the blotches and notice the defined and even angular patterns along the outer edges of the off-colored areas.

That’s it. Those are the only clues I’m going to pass along. Do you know “What’s happening here?”

Stay tuned and I’ll reveal the answer in just a few minutes. Enjoy the next couple of articles while you ponder the possibilities.

Groundbreaker Hydrangea

Here’s a new spin on a popular hydrangea. Groundbreaker is being touted as the world’s first groundcover Hydrangea paniculata.

Groundbreaker Blush

Groundbreaker Greeny

Multi-flowering and a dwarf growth habit make the series great candidates for using as a groundcover in landscapes, mass plantings, border plantings, on slopes and even makes pretty awesome containers. The only get 12- to 16-in. tall, but they spread to at least 2-ft. across. Cold hardy to USDA Hardiness Zone 5.

Groundbreaker Ruby

Groundbreaker was bred in the Netherlands and have already received some prestigious recognition and awards. Groundbreaker Ruby was the runner up for the Plant of the Year at the Chelsea Flower Show this year and last year Groundbreaker received the Golden Award.

This series was introduced by Living Creations and could be hard to find for the next year or so. From my understanding, Plant Addicts has an exclusive on it for a period of time, but with such high demand, I suspect by this time next year it should start to be more readily available. Hang in there—I want some, too.

Fall Trade Events

I really enjoy fall. Not only is there the obvious change in the outdoor seasons, but there’s also a change in growing seasons. With perennials, that usually means shifting from growing plants for same-season sales to producing plants for next year’s sales and managing the transitions from summer to fall and from fall to winter.

I also find this is a good time to recharge my battery by feeding my brain some new information. One source I enjoy that stimulates thought and creativity is by attending trade events. Although most of the upcoming trade events aren't centered around perennials, I think the events listed here could be useful. Click the name of the event for more information.

September 2026

September 1-4, 2026	IPPS Western Region Annual Meeting Salt Lake City, Utah

September 2-3, 2026	Four Oaks Trade Show Macclesfield, Cheshire, United Kingdom

September 9, 2026	Quebec Grower Summit St Hyacinthe, Quebec, Canada

September 10, 2026	Griffin East Coast Expo Lancaster, Pennsylvania

September 11-25, 2026	IPPS International Tour Twin Cities, Minnesota Grand Rapids, Michigan Chicago, Illinois

September 14, 2026	Grey to Green Conference Costa Mesa, California

September 14-16, 2026	Plug & Cutting Conference Philadelphia, Pennsylvania

September 17-18, 2026	International Home Garden Conference Angers, France

September 21-23, 2026	BWI Expo Nashville, Tennessee

Sept. 22 – Oct. 1, 2026	The Garden Center Group Fall Event Cleveland, Ohio

October Trade Events

The number of trade events wanes a little bit in October. Below are the events that I thought would be of interest to some of you:

October 7-8, 2026	Canadian Greenhouse Conference Niagara Falls, Ontario, Canada

October 18-22, 2026	IPPS Southern Region Annual Meeting Houston, Texas

October 22, 2026	IPM Symposium Greer, South Carolina

October 27, 2026	Southern Utah Green Conference St. George, Utah

October 28-29, 2026	California Nursery Conference Modesto, California

Don’t Fall Behind

I really can’t believe it’s nearly September. While compiling the list of fall trade events above, it got me thinking about how critical fall is when it comes to growing perennials and overwintering them for next year's sales.

Then I remembered an article I wrote a few years back (Geez, does 2019 still count as a few years back?) about the different aspects of growing perennials in the fall. In the article, I discuss:

Fall cut-off dates
Bulking
PGRs
Fertility
Irrigation
Pests & diseases
Fall fungicide drenches
Light intensity
Trimming

Here’s a summer planting of baptisia. The plant on the right had healthy roots at one time that had succumbed to undiagnosed root rot pathogens. It’s very important to apply fungicides to crops with unhealthy roots early in the fall to allow time to stop the disease and rebuild the root system before winter arrives.

As you can see, I packed quite a few topics into one convenient article. It’s so convenient, I invite you to read it in its entirety. Follow this link to view the article: "Don’t FALL Behind."

The Answer is ...

I shared this image above and asked if you could identify what's happening to the rudbeckia. I pointed out the leaf-like pattern, the angular outer edges and the coloration of the blotches. Were these clues enough to help you solve this diagnostic challenge? My mind instantly goes to three places when I observe angular patterns on leaves: bacterial leaf spots, downy mildew and foliar nematodes.

Next, I begin asking questions and observing the crop. When I take into consideration these plants are in a greenhouse on benches (off the floor) and learn the starting materials were plugs, not bareroot, I almost instantly remove foliar nematodes as one of the potential causes of this issue.

Bacterial leaf spots can coalesce into larger blotches, but I can’t say I’ve personally observed them covering this much area of the leaf surface. Typically, bacterial leaf spots are small and numerous. To rule out bacterial leaf spots and confirm downy mildew is the culprit, I simply turn over the symptomatic leaves.

And, voilà, there it is. You can see the fungal sporangia on the undersides of the leaves directly beneath and having the same pattern as the symptoms at the top of the leaf. When you see this, it confirms downy mildew is the problem.

Congratulations if you correctly solved this week’s challenge. If you didn’t come up with the right answer this time, now you know what to look for and how you can narrow down your options.

I’ll be at Farwest in Portland, Oregon, this week (August 26-28, 2026). Please stop by booth #8030 (Pace 49) and say hello if you're at the show. I’d love to catch up with you.

My email is paul@pace49.com if you have any comments, article suggestions or if you'd just like to say hello.

Best regards,

Paul Pilon

Editor-at-Large—Perennial Pulse

National Sales Manager—Pace 49, Inc.

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