Episode 14 – Celtic Mythology, Native Holly, and Plant Spacing

Ground Breaking Banter

In celebration of the holidays and in anticipation of Stacey introducing us to “Berry Poppins” deciduous holly in “Plants On Trial,” Rick shares the story in Celtic mythology of The Holly and Oak King. In Celtic mythology, there is a dark Holly King, disguised as a wren, and his twin, the light Oak King, disguised as a robin. Every year at the Winter and Summer Solstices, these two fight for dominance. In actuality, these brothers are two parts of the same thing, the waxing and waning of the yearly cycles of the Earth. The Holly King rules the waning year, from Midsummer to Yule, and the Oak King rules the waxing year from Yule to Midsummer. The Holly King represents darkness, decay and destruction, however, also represents inner knowledge and mysteries. The Oak King, on the other hand, represents light, growth and expansion. These two mighty kings fight a symbolic battle to win the Crown of the year, at Yule when the Oak King wins, and at Midsummer when the Holly King wins. Oak trees are deciduous, meaning that they go into a dormant state during the winter months. English Christmas Holly trees are evergreen, and maintain their foliage year round. As the cold weather approached and the Oak trees lost their foliage, the Holly trees, which had been hidden amid the leafy Oaks now stood out in their full beauty in the barren landscape. At Midwinter, it seemed that the Holly King had won and his brother, the mighty Oak King, now stood naked in defeat. But, the Holly King did not really win the battle, because as the Sun begins to return once again, The Oak King rallies, and begins to re-establish his supremacy, even though it won’t be until Midsummer when the Oaks will once again be in full foliage. The battle continues at Midsummer and the Oak King appears to win, overshadowing and pushing his opponent out of sight, but once again appearances are deceptive as the Sun begins to leave once more and the Holly King rallies and begins to make his full appearance once more. Interestingly enough it is at the time when each King is in his full strength and splendor that he is defeated by his opponent.

Stacey shares with us how oak trees are so thoroughly connected with England but they have only two native species of oak – Quercus robur, English oak, and Quercus petraea, sessile oak. Compare that to North America, where we have at least 55 different species of native oaks!

Are plants able to predict the weather? Stacey quickly dispels that notion but we agree that plants like Rhododendron “react” to cold winter weather by curling their leaves as a protection mechanism (moisture loss).

Word of the day: Thermotropism, noun, plural: photoropisms. Movement or growth response to heat or cold (changes in temperature).
Tropism is an orienting response of an organism to a stimulus. Thermotropism is one of the many forms of tropisms. It pertains to the movement or the growth response of a plant to heat or changes in temperature. The response may be positive or negative. A positive thermotropism is when the growth or movement of a plant is towards the source of heat. A negative thermotropism is when the organism tends to grow or move away. An example of thermotropism is the curling of Rhododendron leaves during cold winter temperatures. Leaf curl in rhododendrons in winter is usually not a cause for concern.

As the air temperature reaches or drops below 32 degrees leaves on rhododendrons they may begin to droop or curl…as temperatures plummet further the leaves curl tighter. Water evaporates from the undersides of rhododendron leaves, and the curling is a mechanism to slow down evaporation and keep moisture. It is not normally cold temperatures that harm rhododendrons in winter, but lack of enough waterThis tendency is called thermotropism…a movement of the plant due to changes in temperature. Another example of thermotropism are plants that actually turn their leaves towards warmth (normally the sun) like Helianthus.

Why: As its name suggests, now is winterberry holly’s (known botanically as Ilex verticillata) time to shine. When you hear the word “holly,” it’s probably an evergreen tree with red berries that comes to mind. Our native winterberry holly, which we are talking about today, is not that. It’s a deciduous holly that loses its leaves in winter. However, that just serves to make its berry display even more impressive! A good specimen of winterberry holly in winter is truly a sight to behold, its grey-black branches covered in masses of bright red berries.

Winterberry holly grows native over the entire eastern half of the US, from Maine to Minnesota and all the way down to Texas and Florida, and in many areas, it’s actually quite abundant. Here in Michigan, you can’t drive any of our highways for long before you’ll catch site of one – they grow in drainage ditches, alongside ponds, and in swamps. Once you’ve kind of trained your eye to spot them, you’ll see them everywhere in winter! That huge native range also bears testament to the climate and temperature tolerances of this plant. It will thrive in hot, steamy, humid climates, as well as in the frigid North.

Who: The Proven Winners ColorChoice Flowering Shrub line has included winterberry holly practically since the beginning, because the owner of the nursery here is an avid hunter and while he was out in the woods in November and the winterberry hollies were strutting their stuff, differences between the color, size, and heaviness of the fruit set made themselves clear. But our early winterberry hollies were the same large plants that you encounter in nature – easily 6-8’ tall and wide. That’s a pretty big plant, especially for home landscaping. So we were long searching for a winterberry holly with a size that was a bit more friendly to your average residential yard and house size, and Mike Farrow was the one who brought it to us in the form of Berry Poppins winterberry holly. We mentioned Mike Farrow on the show before, when we talked about another of his plants, Arctic Fire Red red-twig dogwood. Mike operates Holly Hilly Farm in Maryland, his family nursery founded in 1959, and develops interesting new shrub varieties while he manages the nursery. Berry Poppins winterberry holly is about half the size of wild winterberries, reaching just 3-4’ tall and wide. It is one of very few smaller winterberries available, and one of our best-sellers: once someone sees one covered in bright red berries in winter, they want to have one for their own yard.

How to grow: Any time we’re talking about holly, there’s an elephant in the room, and that’s pollination, so let’s get right to it. All hollies are dioecious, which means that each plant bears either all fruit-bearing female flowers or all pollen-bearing male flowers. Only female plants get fruit, and you must have both a male and a female plant in order to get berries on the female. Fortunately, you don’t need a 1:1 ratio of males to females to get fruit – one male plant will pollinate up to five females. The males and females can be planted anywhere within about 50’ of one another, and while closer is better, this means you don’t need to position the less-showy male plant front-and-center. The male pollinator for Berry Poppins is called, appropriately, Mr. Poppins winterberry holly.

Winterberry holly is quite shade tolerant, but you’re going to want at least four hours of bright sun each day for the best flowering and fruiting. It is not a drought tolerant plant, and will struggle in very dry conditions, so it’s a good choice for rain gardens, wet soils, clay soils, and even along ponds. It is deer resistant, so good news there! If you can site it properly, it’s going to be a very easy-care plant for you. It should not be pruned at all, as there is no time you can do so safely without negatively impacting flowering and fruiting. Lots of people do like to cut some snips of winterberry holly for holiday arranging, and that’s perfectly fine, but it’s not a plant that you would keep trimmed or prune regularly. It is slow-growing, especially for its first couple of seasons, so avoid cutting substantially for decoration until the plant is large enough to withstand it.

It’s far from planting time now that it’s December, but it’s a good time to put Berry Poppins and Mr. Poppins winterberry hollies on your spring planting list, and start looking forward to more colorful winters to come!

Gardening Mail Bag

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Kathy has a spacing question: I will be planting a Picea pungens ‘The Blues’, a Picea orientalis ‘Tom Thumb Gold’, and smokebush.  What would be your recommended spacing?

Spacing questions are always difficult to answer, because spacing plants is both art and science. The science part is fairly straightforward: if your plant tag does not include a spacing recommendation, take a look at the projected plant width. If you live in a cold climate or are planting a hedge, take the smaller of the number range; if you live in a warmer climate or are stretching your budget, take the larger of the numbers; if you aren’t sure, opt for the middle. Let’s take a  projected width of 3-5′ as an example, and we’ll go in the middle with 4′. Divide that number in half – 2′ – and you will place your new plant’s center 2′ from other plants, and/or 2′ away from your home or another structure. 

The art part is where personal preference comes in. Stacey likes her plants to no just touch but knit together into a leafy tapestry. Other people like plenty of space around their plants. So here, make a decision about what you want the final planting to look like, and use that information to make your own decision about how to space. 

Steve has a creative conundrum for us and the audience: Last week you talked about container gardening. I have a broken hot tub that I want to repurpose. Do you have any ideas?

Do we ever! Stacey’s first thought was to turn it into a bog garden. Bogs, which retain moisture but don’t usually have standing water for prolonged periods, are ideal for growing a bunch of interesting plants that wouldn’t grow in more typical garden conditions, like carnivorous plants. If the hot tub still holds water, you could turn it into an actual pond garden, where you could grow water lilies, lotus, and other interesting floating plants. We also open this up to our listeners – if you have a suggestion for how Steve can repurpose his hot tub in the garden, let us know!

Leigh Ann has a great question:

This is sort of a two part question. I have been having fungal issues each year on some of the foliage of my plants. I do my best to water in the morning and to water directly into the ground. Last year I did my best to remove as many dead leaves as possible from my landscape in hopes of getting rid of some of those spores. I still had issues, especially late summer, early fall. So my first question is, what recommendations do you have for fungus issues? And second, I know how great leaves can be for composting, but what if the leaves seem to have the fungus issues?

Any time we hear from someone having fungus issues in their landscape, we have some standard recommendations: make sure the plant is getting enough sun, and good air circulation, and try to pick up all the leaves when they drop in fall so that they fungal spores aren’t just waiting under the plant to reinfect it the following season if conditions allow. However, it sounds like Leigh Ann is already doing this and that there’s a bigger issue: perhaps the plant itself is simply more susceptible to fungus, which sometimes is the case due to genetics, or there’s something about that particular spot that is just favorable to the development of fungus. So, know that it might just be time to transplant and/or replace, trying again with a different plant that’s moreresistant to common fungal diseases. As for composting the leaves, it depends – it should be just fine to go ahead and compost them, but only if they will be completely decomposed by the time you use the compost. The spores must have actual leaf tissue to survive, so if that completely disintegrates in the compost, no problem. If you can wait for complete breakdown of all compost elements, go ahead and add them.

Branching News

  • Public Service Message: As gardeners we know that we live in a bacterial world — bacteria and microbes are everywhere, and we come into contact with them all day, every day” Bacteria and dirt are a part of our life as gardeners. But a simple holiday season public service word of warning. Self-service checkouts may be an efficient way to shop but with convenience comes a dark side. Self-service checkouts are often covered in harmful bacteria — some of which you don’t want to know and I’ll spare you the details…… according to an experiment conducted by the Liverpool School of Tropical Medicine in the UK and backed by the NHS public health officials. Need I say more?
  • Another public service message: Right way or wrong way to put Christmas lights on your shrubs? Think about when and how you’re going to take them off. A tangled mess can do damage to buds and stems so put them on to be taken off.
  • Viva Magenta is the Pantone color of the year! 
  • Rockefeller Christmas Tree is up again!
  • It’s Christmas Time again! I have two words for you……Chicken Wire!
  • There is a job opening for someone good at rat/mouse/mice control in New York City!