Episode 23 – How to Keep House Plants Happy and When to Prune Mountain Hydrangeas

Ground Breaking Banter - Rick

As winter wears on and we can all use some tropical thoughts. Stacey and Rick discuss tropical plant care this week. Rick prefers calling them “indoor tropicals’ instead of houseplants because that sounds “like they are captives, under house arrest.” Whether it’s caring for your “houseplants” or planning “tropicals” for your deck and patio this summer, “tropical plants” are an important element of our life with plants.

Stacey and Rick discuss watering of indoor tropicals. Avoid watering based on a schedule. Stacey says determine water needs by the weight of the pot. Rick shares that the mistake a lot of people make is a “little bit of water” every week. This causes the upper soil profile and roots to be wet and the roots in the center and lower part of the pot to be dust dry. This speeds deterioration of the plant. 

illustration of the harm caused by watering frequently with small amounts

Stacey and Rick agree that “cache pots” are a good solution.

A plant in a pot that has drainage holes in a Cache pot

Humidity is important for indoor tropical plants. Rick was looking at synonyms for “tropical” and they were “steamy, sweaty, equatorial, hot, lush” etc. which does not describe our indoor living spaces with forced furnace air in the north. Move the plants away from a heat register.

Stacey and Rick agree that dusting and cleaning the foliage will improve plant health and their ability to photosynthesize. Rick is not a big fan of leaf shine and reveals (admits) he has shined plants with Miracle Whip from time to time.

Rick reveals some of his favorite “indoor tropicals” (houseplants). These are Proven Winners leafjoy varieties:

The 2023 Houseplant of the year Feeling Flirty® tradescantia is easy to grow indoors and great to use outdoors in containers during the summer.

Word of the day: to anthropomorphize. (verb) to attribute human form or personality to something that is not human. Are you talking to your plants? A survey/study that nearly 50% of people talk to their plants from time to time? We’ll look at it in branching news. And here is a fun read from the Washington Post

We love using tropical plants outdoors after frost (here north of the Mason Dixon line) during the growing season in containers, on the deck, porch or patio. There are a number of Zone 7+ and warmer plants in the Gardening Simplified catalog!


Why: What better way to celebrate Valentine’s Day than with a plant that wears its heart on its sleeve – or at least, right there in its name? Happy Face Hearts potentilla gets its name from the candy-pink petals, each dotted with a stream of cream, white, or yellow. Plus, it’s also the perfect plant to talk about in mid-February because it is extremely cold-tolerant: like most potentillas, it’s hardy all the way down to USDA zone 2. That’s areas that can reach as low as -50°F in winter, which is pretty darn cold. Sometimes, you’ll see the name “shrubby cinquefoil” associated with the plant, but potentilla is the more commonly used name – probably not least of all because few people want to attempt to pronounce “cinquefoil,” which comes from the French for “five-leaved.”

Potentillas in general get kind of a bad rap for being “gas station plants” – in other words, ho-hum staples of generic landscapes. But that’s really not a fair assessment, especially not for Proven Winners ColorChoice potentillas. Like all of our shrubs, we trial and test them to make sure they outperform the other potentillas on the market, and that means bigger flowers, brighter colors, better disease resistance, and non-stop blooms. If flowers are what you are after, and you live in a colder climate, you really can’t do much better than the Happy Face series of potentilla. Here in our West Michigan trial gardens, they start blooming in May and do not stop until well into autumn. And it’s not like it’s just a few flowers here and there – the plants are pretty much covered in big, colorful blooms all season without you lifting a finger. No deadheading, trimming, or pruning required.

Happy Face Hearts potentilla grows as a low, ground covering mound, about 1-2’ tall and wide. It’s a woody plant, a shrub, but its stems are mostly fine and not really thick and woody; it’s more like it has a sturdy woody base. It’s a great plant for placing at the edge of a landscaping bed, lining sidewalks, or just keeping weeds down.

Who: Happy Face Hearts potentilla was developed right here in West Michigan. Like many other plant development companies, we’re all looking for the holy grail: a true pink potentilla that keeps its color all summer. Yes, it’s true: unfortunately, all of the colorful potentillas, which is to say any that are not yellow or white, tend to lose their color during the height of summer, when the tempertures are high and the days are long. This is because plants synthesize their pigments at night, and when those night time temperatures aren’t dipping very low, potentilla just isn’t able to produce those true, vivid pigments. But not to worry – this is a temporary condition, and once the nights start to get a bit longer and cooler, the color returns like it had never left.

So we were looking and testing for pink potentillas with a good, bright, rich color that would hold on to that all summer. And while Happy Face Hearts will also blanch, or turn white-ish, if the summer is very hot, it’s as close as you can get to good, reliable color. We also look for health foliage that resists powdery mildew and spider mites, two issues that plague more conventional potentillas, and you’ll see that Happy Face Hearts has glossy, dark green foliage that looks great on its own and complements the flower color, shape, and size.

How to grow: Potentilla is a sun-lover, and while it can take part shade, planting it in full sun (6+ hours of sun each day) will give you the most prolific blooms. If you live at the hotter end of its range, some shade during the afternoon may be a good idea, and may also help maintain flower color at the height of summer.

Once it is established, potentilla is very, very drought tolerant. If you look closely at its foliage, you’ll see its covered in fine hairs – these help minimize transpiration, in other words, water loss through the foliage. They trap that water vapor and keep it near the plant. So while you’ll want to water it for its first season or two to develop a good root system, once that’s in place, it can pretty much be left alone.

Potentilla blooms on new wood, and can be pruned in spring if you wish. Overall, it doesn’t need regular pruning, but once it has been planted for five or so years, you may want to take out the oldest branches – this isn’t necessary, but it will help keep the growth fresh and young, which is much more floriferous than the very old growth. It’s just a simple thing you can do for the very best looking plant.

Finally, great news for everyone with deer issues – potentilla is one of the most deer resistant flowering shrubs you’ll find. It’s so deer resistant, in fact, that it’s a part of our new Deer Proof program – a select group of shrubs that are the least-favored by deer. So when you look for Happy Face Hearts potentilla – or Happy Face Yellow or Happy Face White – at your local garden center this season, they will most likely be in this special container to really show how deer resistant they are.

Gardening Mail Bag - Stacey

In the spirit of upcoming Valentine’s Day, I ask Rick if he and his wife garden together. And we discover that when it comes to gardening, both of our spouses are similar: they are the organized, exacting ones who make plans and get out the measuring tape when it’s time to plant, and we’re the freewheeling, get it in the ground and we’ll figure everything out later types. And really, it’s a perfect combination in the garden and in life when your strengths and weaknesses, your goals and approaches to problems complement each other. So, thanks and Happy Valentine’s Day to our ever-patient, amazing spouses!

Catrina writes with two questions: If I am considering relocating and would like to move somewhere warmer so I can grow more but not lose the ability to grow plants/trees I can grow today (like apple, peach trees and berries). What hardiness zone would you recommend? I currently live in zone 5b. Also, if you had the choice to move anywhere in the US, what hardiness zone/state would you pick and why? 

Great questions! To answer your first one, Rick and I agree: somewhere in USDA zone 7, say, Virginia or Northern/Western North Carolina. In these areas, you still get enough cold temperatures to provide the chilling requirements that these species need in order to flower and fruit properly, but you generally will miss out on the unexpected spring frosts that can kill the flowers and/or developing fruit and ruin the crop for the year. It’s not to say they will never happen, but they do tend to be a less frequent occurrence for home gardeners.

As for our ideal climates, I pick either the northern California “banana belt,” where it’s mild enough to grow tender plants but not terribly hot, or the San Diego area, where I could achieve my dream of growing citrus and avocados, as well as members of the amazing Proteaceae, or protea family, which is native to Australia and South Africa. Rick picks Virginia, because he loves hot and humid weather, and history. Thanks so much for asking!

Mary writes: Two years ago I planted two of the Proven Winners Tuff Stuff Red mountain hydrangeas on the south side of the house. I fertilized with 12/12/12 last spring. They did not bloom except for a few meager flowers. I did not trim them this fall. They still have dead leaves on them. Should I prune them? They are only about 2 feet tall about how I want them. The rest of the perennials around them all did well. Is it too sunny? They are in front of an open porch so no reflection from the house.  Any suggestions?

Tuff Stuff hydrangeas bloom on both old and new wood, and from what you describe, it sounds like last year, your plant only bloomed on new wood. Even though the Tuff Stuff series has better flower bud hardiness than their cousins big leaf hydrangeas, their old wood buds – which are present all winter – are still susceptible to cold damage. Contrary to popular belief, it’s not usually so much winter cold that damages or kills the flower buds, it’s spring frosts that occur later in the season, after the new growth has been gradually coaxed open by the warm days of April, that are the problem. 

Definitely do not prune your plants, now or at any time of the year, except to remove any dead wood in spring. And this coming spring, in April and May, if you are seeing green growth on your plant and a frost or freeze is in the forecast, cover the plant with a blanket for the night to keep the freezing air from contacting the tender growth. Here’s a quick video on the difference between old and new wood, and what it means for hydrangea blooming. 

Branching News - Rick

  • It was a somber Groundhog Day in Canada, as Fred la marmotte – the beloved groundhog who predicted weather – was found dead hours before he could take part in his annual tradition.
  • This woodpecker has been busy! Creating holes in a home’s siding — holes in which to store food for later eating. In this case, that food was mostly acorns. But unfortunately for all involved, the acorns weren’t staying put. Instead, they were falling into the empty cavities inside the walls. A deluge of 700 pounds!
  • Stacey and Rick discuss Acorn Woodpeckers. Here is a great link to check out!
  • 48% of people report talking to their trees and/or plants. Of those who do, one in five say they speak to their plants every day. Two-thirds believe it helps them grow. Nearly one in four even say they have kissed their plants.
  • It was “mint” to be. A new study by researchers at Michigan State University may unveil the first step in creating all-natural medicines and replacing harmful chemicals, all from a common herb. The mint family. Rick says maybe the students will receive “encourage-mint” from the results. Maybe even an endow-mint for the college. One thing’s for sure, they did well on their assign-mint!
  • A statue believed to be around 2,000 years old has been found in Rome during repair work to a sewage system.The life-sized marble statue portraying a male figure dressed as the mythological Roman hero Hercules was discovered in a public garden in Rome during works to restore sewage pipes, in the surroundings of the archaeological area of Appia Antica. Rick says good thing they saved it, destroying it would have been a “monumental error.” Even after this long the discovery is within the “statue” of limitations.
Pink rose of Sharon flowers bloom on a plant with variegated foliage.

Episode 92 – Weeding by Example

Ah, weeds – maybe the #1 thing that discourages people from gardening. But weeds are interesting and become a lot easier to manage when you apply some basic IPM principles. Featured shrub: Sugar Tip rose of Sharon.

Read More »