Episode 38 – Favorite annuals, plant innovations, and a celebration of pollinators

Ground Breaking Banter - Rick

In the flower business, we had a saying: “annual plants don’t come back so you come back.” Annuals are great because there are easy-to-grow favorites for both new and experienced gardeners. They’re about as close as you can come to instant gratification in gardening, whether you plant them to temporarily fill in bare spots in established gardens or refreshing containers through the season. If you want a lot of blooms – and who doesn’t?! –  annuals are your answer. They put all of their energy into developing flowers.

Technically speaking, “true annuals” are plants that germinate, flower, set seed, and die all in one season. Their ultimate goal is to reproduce themselves (set seed), which is good news for gardeners because most annuals will flower like mad until their mission is accomplished. However, most people now use the term “annuals” to mean  any plants you grow during summer that die when it gets cold – even though they might be perennial (able to return year after year) – in warmer climates. 

Growing annuals is the perfect way to experiment with new plants and color schemes without making a long-term commitment. So don’t be afraid to take a little risk with the color, shape, size, or texture.

Now, about the cost. Think of it this way: if you spend one day at an amusement park, you’re going to pay at least $60 or more for a pass, plus parking, refreshments, and souvenirs.  Or take a few hours at the movies as an example: a ticket is $12, $8 for popcorn,  $6 for a drink,  $5 box of candy. You’d be in $31 per person for just a couple hours of entertainment. So spending $100 or so on annuals that will give you color all summer is a deal!

Take advantage of the advances in flowering annuals today! In the 70’s and 80’s, I would spend hours in the garden center deadheading slimy sickeningly sweet spent petunia blossoms. I had a “drill sergeant” as a mentor named Doris. I was trained and supervised as a youngster at the garden center by an owner named Doris who was a Navy WAVE from 1943 to 1946 during WWII. The acronym WAVES meant Women Accepted for Voluntary Emergency Service and those who volunteered had to serve for the duration of the war plus six months. On July 30, 1942, President Franklin Delano Roosevelt signed Public Law 689 creating the women’s reserve as a part of the Navy and war effort. As a 18 year old kid deadheading flowering annuals and setting displays at the store there was no question who was the captain of the ship in my work area. To avoid scuttlebutt, everything was to be ship-shape. Each day it was ahoy and all hands on deck for inspection. Something like a floral boot camp. You could hear her coming, working in the plant area in a dress and heels with a floppy sun hat and gloves. Click click click you would hear the rapid footsteps of her heels on the concrete floor as she approached and everyone stood at attention. I was trying to stay out of the brig even though it was only a rumor that one existed. After inspections she would type a report on site using an old typewriter in the office. Rat tat tat tat it sounded like a machine gun as the keys would strike the paper. She would rip the paper off the typewriter and distribute her orders for the day. She would then jump in to the work with the rest of us pitching and slinging plants into position and identifying those that needed to go to “sick bay” for recovery or discounting. At the time she was in her early 60’s and it was tough to keep up with her pace. At the end of the day she would go back to the typewriter to hammer out a synopsis of the work yet to be done and where improvement was needed. The notes were random and urgent with a mix of capital letters and odd spacing giving them the feel of a hybrid between a Western Union telegraph and a ransom note.

Things have come a long way: we now have sterile self-cleaning, heat tolerant, vegetatively-grown petunias that need virtually no maintenance, like the Supertunia Vista series – and especially the beloved Supertunia Vista Bubblegum.  Supertunia® are developed from cuttings, not seed. Since Supertunias® do not come from seed that also means that they do not produce seed. The Proven Winners® petunias are more floriferous because all their energy is put into flower production, not seed production. In contrast to the Wave™ Petunias, Supertunia® have shorter stems that contain more leaves and flowers and have better heat and humidity tolerance during the heat of the summer. Supertunia® petunias are better suited for container and hanging baskets over Waves™, because they do not create as big and dense of a root ball and will last longer in their container. Also Proven Winners® petunias have a better spilling habit in pots and baskets creating a beautiful flower display.

Necessity is the mother of invention in plant breeding as well as other fields. Take, as an example, disease resistance in Impatiens walleriana (or as I was taught by Doris “busy Lizzy”). In 2012, impatiens disappeared from the market due to a disease called impatiens downy mildew. IDM spread like wildfire seemingly overnight, stripping plants of both foliage and flower until yellow stalks are all that remained. It spreads by water splashing from infected plants and by windborne spores from infected plants. While its temporary removal from the market disappointed a lot of gardeners, it also spurred the development of new, disease resistant impatiens, as well as the introduction of new species that tolerate shade, like Rockapulco® or Beacon or SunPatiens® and in shade plants choices like Heart to Heart caladiums.

Still need some inspiration? Click here to see Stacey and Rick’s top ten annuals.  

Why: Speaking of how plant breeding can completely change the way you think about a plant reminds me of this truly game-changing viburnum that is one of the best reblooming shrubs – never mind viburnums – that I have ever seen. And that’s Steady Eddy viburnum. It’s a doublefile viburnum, known botanically as Viburnum plicatum var. tomentosum, and it derives that unusual name because the flower clusters emerge one on either side of the branches, forming two neat lines. This unique trait gives the plant a very distinctive look when it blooms, and now, here in Michigan, at least, doublefile viburnums, including Steady Eddy, are blooming like crazy.

Many people mistake doublefile viburnums for hydrangeas in bloom. It’s easy to see why: double file viburnums come in both mophead and lacecap flower versions, depending on the variety. But botanically speaking, which is to say when you actually look at their flower parts, they are very different and not remotely related beyond the superficial resemblance. Conventional doublefile viburnums bloom just once in late spring, but Steady Eddy is not content to be like the rest. No, after it flowers in late spring, it takes the briefest of rests and comes back to bloom again and again, all through summer. In fact, if it is kept growing vigorously and free of stress, it will bloom nearly continuously, and abundantly. It really is a high performance flowering shrub for people who obsessed with flowers.

Who: Innovative new shrubs can only come from innovative plant breeders, so it’s no surprise that this comes from Dr. Tom Ranney of North Carolina State. He and his team in the mountains around Asheville, North Carolina have developed some of the most innovative shrubs in the Proven Winners ColorChoice line: Invincibelle Spirit, the first pink ‘Annabelle’ hydrangea, Double Take thornless quince, and Perfecto Mundo reblooming azaleas, to name just a few.

How to grow: Hardy in USDA zones 5-8, Steady Eddy viburnum is an excellent choice for sun or part sun (4-6 hours of sun per day). In too much shade, its blooming will be severely impaired. It’s not particularly finicky about soil, growing well in an average, well-drained soil. Like the majority of viburnums, it is drought tolerant, but dry conditions will also impair blooming. Fertilizer is not imperative, but applying fertilizer monthly from early spring through about late July will boost the blooms substantially. Overall, this is not a plant that should need much, if any, pruning. It certainly does not need pruning in order to rebloom, and it takes on a nice, natural shape that doesn’t require improvement. If you do wish to prune, though, the first bloom in spring is on old wood, so prune after that. Pruning may delay rebloom, but as it puts on new growth, those new wood flowers will develop and open in time. 

If you’d like to add Steady Eddy viburnum – or any of the 320+ Proven Winners ColorChoice Shrubs – to your garden or landscape, you’ll find a list of local retailers here

Gardening Mail Bag - Stacey

Double Play Doozie spirea should be easily able to tolerate full sun in USDA zone 7b, so I suspect the issue is watering. It surprises many people that plants wilt from both underwatering and from overwatering, so before you make any decisions on moving them, consider the moisture situation. You say you amended the soil – was it thoroughly mixed with your native soil? If not, that can lead to a bathtub effect where water stays around the rootball for prolonged periods, leading to wilting. Aside from that, you are the one who would best know if they are getting too much or too little water and can adjust accordingly. 

As long as you put down the cardboard with a wide berth around the hydrangeas – say, a good 2′ or so – it won’t hurt them. However, in a warm, humid climate like yours, the cardboard is unlikely to last long enough to accomplish the weed control you need – especially if the weed is indeed Ornithogalum umbellatum, also known as star of Bethlehem, as we suggested. It’s very difficult to control, and you’d need to keep a thick layer of cardboard over the area for several months of hot weather for it to have any effect – especially when the weeds go dormant and the bulbs nestle into the much cooler soil to avoid the stifling effect intended by using the cardboard.  

Incrediball hydrangeas are a selection of our North American Hydrangea arborescens. As this plant is native to much of the country, not surprisingly, it has certain relationships with insects, and that’s what you are seeing here – the work of the hydrangea leaftier. That’s leaf tie-r, as in one who ties, not leaf “tier”, like a tier in a cake. This native moth lays an egg in the emerging foliage of Hydrangea arborescens and when it hatches, a tiny caterpillar emerges. It quickly sets out to tie the leaves together to make a safe, protected home for itself while it gets to work eating the even more tender emerging new growth of the plant. The best way to manage them is to simply break open the tie and either squish the little caterpillar inside, or leave it open and let the birds or a predatory insect take care of it. Hydrangea leaftiers are not terribly harmful to the plant’s health, but a large infestation can definitely hamper blooming, so it’s a good idea to go ahead and break them open and let nature take its course. Read more about this interesting native insect (we hesitate to call it a pest, per se) here

Do you have a question for us? We’re happy to help! E-mail us or use the contact tab above.

Branching News - Rick

Today, we’re joined by Mike Connor, an ISA certified arborist and beekeeper for over 50 years. As you will hear, Mike is absolutely passionate about conserving pollinators, including our native bees that are too often overlooked in the conversation about bee health. One of Mike’s mottos is “Plant a tree, save a bee” because a flowering tree like a linden provides a huge amount of food for bees in a very small space. Please watch the video below or tune in on your favorite podcast platform, because Mike’s knowledge of pollinators is contagious! Learn more about him, or contact him for tree services in the West Michigan area, at his website.

A hydrangea in a low decorative container covered in pink and purple mophead flowers.

Episode 96 – Garden Regrets

Regrets? We’ve had a few, and maybe you have too, which is why we’re dedicating this episode to the things we wish we had – and hadn’t – done in the garden. Featured shrub: Let’s Dance Arriba reblooming hydrangea.

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