Did you know that the Dwarf Alberta Spruce (Picea glauca ‘Conica’) that is commonly found in cold-climate commercial and residential landscapes is a naturally occuring dwarf of the white spruce species (Picea glauca) and was discovered by J.G. Jack and Alfred Rehder in 1904 in Alberta, Canada? (Dirr, Manual of Woody Landscape Plants, 5th Edition, 1998).
Neither did I, until fellow garden blogger Laura Hayden (@DurableGardener) and I ran across this odd little tree outside our hotel in St. Louis this past weekend where we attended the National Green Centre trade show. I mistakenly identified the unusual growth at the top of the tree as a sport, but Laura correctly pointed out that it wasn’t a sport, but a reversion to the parent species. At some point, a branch of this young tree reverted back to being a full blown species White Spruce, a tree with a much larger and looser habit than the small, dense ‘Conica’. The people responsible for the landscaping at the hotel failed to realize the problem and didn’t prune the reverted branch out.
I hope I remember to drive by this hotel each time I visit St. Louis to check on the progress of this tree. Something tells me that someone will find this abnormality too distasteful and have it pruned out. But I’d definitely be interested in knowing what would happen if it were left to grow into something that might fit more into a Seussian adventure than alongside a hotel parking lot.
This past weekend, I had the opportunity to attend the National Green Centre (NGC) trade show hosted by the Western Nursery and Landscape Association in St. Louis. As an optional event at NGC, Dr. Michael Dirr led a plant walk through the grounds of the Missouri Botanic Garden (MoBot). Our small group (about 30) was made up of industry professionals — arborists, landscape architects and designers, growers, breeders, wholesale nursery owners, Master Gardeners, and others.
We’ve had unseasonably warm temperatures this past week after narrowly avoiding a frost the first weekend of October, but I haven’t allowed the warm, sunny days to lull me into the false belief that cold weather isn’t right around the corner. It is undeniably time to prepare the garden for winter, and one of the first steps is deciding which of the tender annuals I will overwinter indoors and which I’ll let succumb to the first heavy frost.
Unless you have a conservatory, your best bet with larger tropical plants (like caladium, elephant ears and bananas) is to store their root/storage organ in a dormant state over the winter. Coleus (Solenostemon sp.), on the other hand, can’t be overwintered in a dormant state. In order to save coleus from one year to the next, you have to take cuttings of your existing plants to create new, smaller plants that you grown indoors during cold weather.
Luckily, if you can provide enough light and water, coleus is an easy plant to grow indoors. Here’s the process I use for taking cuttings.
You’ll need the following:
- Small plastic cups, with 3-4 drainage holes punched in the bottom.
- Potting medium (I use MiracleGro potting soil so I don’t have to deal with fertilization over the winter.)
- Rooting hormone (I use Rootone.)
- A pair of small hand pruners
- Flat trays (enough to hold all the plastic cups)
- Coleus plants (You can use the coleus you’ve grown in your garden, or even discounted plants that still may be available at your local garden center.)
First, pre-moisten the potting medium in a large bucket and fill each plastic cup with soil to about 1/2-3/4 inch of the cup rim. Filling the cups to full will make watering the coleus a more difficult and messy process throughout the winter. Once you have the soil medium in the cups, you’ll then need to select the branches from your coleus plants.
The best branches to choose are those with multiple side shoots that terminate in a multiple leaf cluster. If the branch doesn’t have side shoots, you’ll only get one cutting per branch. If you cut more than one or two branches at a time, be sure to have a vase of water in your prep area. Coleus rapidly dehydrate after cutting, so it’s important to keep them in water if there is any significant delay between cutting and transplanting.
Using your hand pruners, cut each side branch off the main stem, leaving about 3-4 inches of stem down from the terminal leaf cluster. The same can be done for the leaf cluster at the top of the branch.<
Carefully prune the side leaves off the stem, leaving at most four leaves at the top of the stem. The goal is to have enough leaf surface to help feed the new plant, but not so much that it’s impossible to keep alive during the rooting process.
Dip the bottom inch of the cutting into the rooting hormone, making sure it is thoroughly covered. Be careful to avoid eye or mouth contact with the rooting hormone, as most contain a fungicide that is toxic if ingested.
Gently insert the cutting into the potting medium, one cutting per cup. Coleus stems aren’t very sturdy, so it takes a bit of practice to slide the stem into the potting medium without breaking it.
On some varieties of coleus, the terminal leave cluster includes two larger leaves. On these varieties, I tend to pinch half of each of the larger leaves off to reduce the amount of plant material the cutting needs to support.
Continue this process until you’ve inserted all your cuttings into the potting media. Make sure to water the cuttings lightly, and continue to do so as necessary. In the beginning, watering is required every day or so. Once the plants have established new roots, watering can be scaled back to about once a week. Be sure to monitor them regularly, as the coleus will droop almost instantaneously when they reach a critical moisture threshold.
Coleus also need bright light to thrive. I grow mine under timer-controlled fluorescent plant lights that provide 12-14 hours of light each day. If you had a sunny window and just a few cuttings, you could probably avoid the need for plant lights.
This year, I took 105 cuttings, including the following:
- ‘Religious Radish’ (18)
- ‘Rustic Orange’ (8)
- ‘Aurora Peach’ (8)
- ‘Trailing Dark Heart’ (27)
- ‘Big Red Judy’ (8)
- ‘Pat Martin’ (7)
- ‘Trusty Rusty’ (9)
- ‘Henna’ (8)
- ‘Alabama’ (5)
- ‘Twist and Twirl’ (1)
I’m hoping to add a few more cuttings from my own garden to this list, as well as a few new varieties from gardening friends. Last year was my first year overwintering coleus, when I took nine cuttings. These cuttings grew so well, I had to take two additional sets of cuttings during the winter. As a result, I ended up with about 70 plants by spring. With 105 cuttings (and more to come) this year, I’ll probably have coleus to spare for next year’s garden.
When my in-laws moved to Illinois from Michigan, they dug up some of the plants from their landscape to bring some of their garden with them. When my mother-in-law asked me if I wanted a division of an iris that had been in their family for nearly 60 years, I jumped at the opportunity. She told me that this iris had been growing on the farmstead her family purchased in the late 1940s, and had been transplanted to different family homes over the years.
While enjoying a day of furlough from my university job, my son and I hiked through part of Crystal Lake Park in northeast Urbana, 90-acres of land surrounding Crystal Lake, a body of water formed more than 100 years ago by the damming of the Saline Branch. The park is home to Busey Woods, the remains of the Big Grove oak hickory forest.
Some of the stately oak and hickory trees that made up the original Big Grove still stand, their craggy trunks rising solidly out of the snow covered park. But my eyes and lens continually focused on a tree I’d never seen before. It lined the banks of the lake and river that feeds it, its branches heavily drooped with the most unique combination of fruiting bodies.
When we think about the bounty of our gardens, we envision perhaps a bushel basket full of freshly-picked sweet corn or a bouquet of fragrant wildflowers. We may remember the visual beauty of our landscape and how it serves as our refuge from the hectic nature of our everyday lives.
But, for me, one of the greatest products of the garden is the abundance of words that have been written by gardeners throughout the centuries as they embrace the beauty of nature, fill themselves with the sense of accomplishment that comes from tilling the soil, and understand the cycle of life that underlies all their horticultural endeavors.
Before the days of e-commerce, I could spend copious amounts of time browsing bookstore bargain tables, looking for that gem that didn’t receive mainstream attention, but nonetheless contained valuable information or inspiration in its pages. Since Amazon.com launched its Used and New service, allowing third party booksellers to shop their titles through the Amazon website, I’ve been addicted to finding deals on gardening books to add to my collection. My personal favorites are those titles selling for a penny (plus $3.99 shipping).
In yesterday’s blog post, I identified a tree sapling growing in one of our borders as a crabapple (Malus spp.), but it occurred to me this morning that we don’t have any crabapples in our garden or nearby yards that display deep red fall color. It didn’t make sense that we would have so many crabapple saplings that didn’t match the surrounding trees. Could it be that the saplings displayed different fall color than their parent? It’s certainly possible as seed propagated children often diverge from their parent’s characteristics.
When we bought our house almost a decade ago, the narrow strip of turf along the north side of the driveway was interrupted by a row four small trees, one crabapple and three sweetgum (Liquidambar styraciflua). From their size when we moved in, it appeared they were planted by the original owner when the lot was developed seven years earlier. Sweetgum was not a tree I was familiar with at the time, and the dried seed pods (“syncarp of dehiscent capsules” according to Dirr) on the juvenile trees seemed quite ornamental in the early spring. For those of you who have lived in proximity to sweetgum, I do not hold you in contempt for snickering at that last sentence.
Just spent a few minutes over at TED.com learning about the Millennium Seed Bank. As a plant lover (and as a human being interested in the continuation of our species), it’s comforting to know that some have the foresight to protect the diversity of plant species on earth.