Plant Propagation by Softwood Cuttings
It’s been such a wonderful gardening season! I have tried several new plants this year that turned out to be real stunners! As it happens, I got my three favorites from garden centers in a large city almost two hours away from my home. There is absolutely no guarantee I will be able to find these plants locally next year, but I certainly do want to grow them again, and I know that two, possibly three of them,
will not survive winter. What to do? Take cuttings and grow them inside, of course!
Many gardeners are completely intimidated by the whole propagation thing, when in fact for many plants it couldn’t be easier. This week I took cuttings from:
Salvia, Mystic Spires:
a gorgeous hybrid between Salvia, farinacea and Salvia, indigo spires, which combines the best qualities of each parent: neat, non flopping habit and continuous bloom from May to frost from farinacea; deep blue color and extremely long, showy flower spikes from Indigo Spires; and a height that is in between the two: about 24 to 32 inches.
Euphorbia, Diamond Frost:
a splendid new plant that looked like white, frothy snowflakes all summer long no matter how hot, dry, or wet it was. It’s the south’s answer to baby’s breath, only better. There’s not much info on this plant yet, so I am trying the cutting method outlined below with high hopes, but no guarantees. (It’s a close relative to poinsettias, so I decided to use the same propagation method. So far, the cuttings look great. I’m encouraged!)
Duranta, Cuban Gold:
A bushy, lightly thorny plant with chartreuse and gold variegated leaves, that makes blue flowers; although I kept it cut short instead of letting it bloom. I will move it next year so it can flower too.
All three winners. All three worth overwintering.
Now, you may not have these particular plants, but you can use this same technique for many, many annuals, perennials, tropicals, and even shrubs! I will be starting roses, weigela, and other deciduous flowering shrubs when the weather gets cooler using this same technique (only outside). Stay tuned!
Assembling a Simple Light Shelf :
First, I took a fresh look at a set of Rubbermaid plastic shelving I have in my unheated basement. The shelves are deep enough that I can slide four nursery flats onto each shelf. It has five shelves, so that means it will accomodate 20 flats of plants. That ought to be enough for, not only my cuttings, but the seeds I’ll be starting in late winter. Then I went to Lowe’s and bought five sets of fluorescent shop lights, at less than $9 each. I used chains and S hooks to hang the fixtures above each shelf, plugging them into a power strip. Presto! A light shelf set-up for less than $100!! I will place solid plastic trays under the flats to catch water, so the fixtures don’t get wet during the winter. I will also hook them up to a timer so that the plants will get eighteen hours of light per day throughout the winter.
Preparing the Containers:
On to the garden. I filled gallon plastic containers with potting soil, packing it tightly into the pots, and leaving about 1/2 inch of headroom in each pot to accomodate water. Using a skewer, I stuck two holes into the soil about three inches apart, running the skewer all the way down into the soil. This makes it easier to stick the cuttings without bruising or breaking the stems. I have learned in the past, that it’s very important to provide the plants with plenty of root room. The deeper the pot is, the better they do.
Then I went to the Garden and took Cuttings:
Salvia and Duranta: I looked for fairly thick stems that had not yet grown woody. I cut them long enough for each piece to have four sets of leaves. I cut the two bottom sets of leaves off the stems, removed blooms, and then stuck the cutting into the skewer holes I made right up to the base of the bottom set of leaves. I put two cuttings per pot, so if one fails, I have another for insurance. If they both make, the plants are easy to divide later.
Euphorbia: This plant was different. It doesn’t have the same type of structure that most plants have. The leaf joints are very far apart. So, I took four to six inch tip cuttings, and stuck the skinny little stems into their appointed holes. I am guessing that this plant will root all along the stem, not just the joints. As I said before, there’s not much info around, so I am experimenting. I’ll keep you posted!
Then I watered each pot thoroughly so that the soil was saturated throughout the pot. I let them drain for about 30 minutes to get rid of all excess water. I put the pots of salvia in shade outside. I will not put them into sweat boxes because salvias rot easily in too moist conditions. I will make sure they get water everyday, though.
I put the Duranta and Euphorbia cuttings into “sweat boxes” outside on my shady back porch. I use clear plastic rubbermaid storage boxes for this purpose. I placed the pots in the lid, and then turned the box upside down over the plants, snapping it into the lid. There should be a cloud of humidity inside the box, but only slight dripping of water going on. It’s been several days now, and so far, all the cuttings look fresh and are not wilting: a very good sign. I will do absolutely nothing to the pots in the sweat boxes for several weeks until I see signs of growth. If you don’t have plastic storage boxes, you can try cutting the bottoms out of 2 liter drink bottles and placing one over each pot, or you can simply use plastic bags with a stick inserted in the pot to keep the bag from collapsing onto the plant. If you decide to invest in some boxes, get the deep ones! You can start cuttings in bigger pots and have plenty of headroom in them.
When I see growth on the cuttings, I’ll take them out of the sweat boxes and begin watering and fertilizing the plants. By then, it will likely be time to bring them in to the basement and set them up under the lights. For the winter, I will keep them watered, and feed them half strength liquid fertilizer twice a month. Come spring, I will harden them off and move them outside. With a little luck and good weather, I can take even more cuttings from them in early spring and have plenty more plants to move out into the garden.
This may seem like alot of work and trouble, and I suppose it is in a sense. But once Christmas is over, I get dreadfully antsy for spring to arrive and it’s a good thing for me to have some inside gardening chores to keep me distracted. Besides, I’ll want to spend my gardening dollars on more NEW plants next year! Try it! You’ll like it!