I’ve been puttering around with my garden for almost 30 years, and I’m embarrassed to say that I have yet to figure out the best way to handle SPRING CLEANUP when the garden contains ephemerals, spring flowering bulbs, and finnicky perennials besides the regular smattering of trees, shrubs and ornamental grasses.
I enlist the help of a landscape crew for this huge job, and I only want to have them for one day. If I only had the trees, shrubs, ornamental grasses and the tougher perennials, then it’s an easy decision. Schedule the work for March when the daffodils and tulips are visible, but still small, so they can be avoided, and the grasses and perennials are still dormant. The workers can easily maneuver without damaging any of your prized possessions.
Unfortunately, I have some ephemerals that are close to the ground, some that are just starting to appear, as well as some perennials like Oenothera fruticosa ‘Fireworks’ / Evening Primrose with rosettes of basal foliage hugging the earth. If covered with mulch, they will likely be smothered, and die. Every year, I try something a little different, and I have yet to figure out a good system that works. Yes, I’ve smothered plenty of plants in the past. One year, I decided to wait until all of my perennials were up, but by that time, I was inundated with weeds. In addition, the workers definitely damaged some of the plants, because there simply was no safe place to step. I can assure you that fresh mulch in the spring significantly cuts down on the weeds.
This year, I’m trying something new. I am having my crew arrive in March.
After removing the winter debris, we will sparingly broadcast Snapshot to help reduce the weed seed germination. * I will rope off areas with tender plants that are to be avoided, and allow them to spread mulch everywhere else. If I had enough compost, finely chopped leaves or pine fines, I would use that instead of mulch, but mulch is readily available, and less expensive than pine fines. Hopefully, they will leave some mulch behind so that I can spread the mulch on the roped off areas a bit later in the season. Where I have been growing Carex pensylvanica instead of grass, I will try just a very light dusting of mulch. This Carex spreads by underground runners, and I don’t want to smother the new growth trying to make an appearance this year. I’m curious to see if this system will work any better.
CICADAS ARE COMING
Several of you have asked what to do about the cicadas. We have all seen the articles. Some recommend protecting young trees and shrubs. I have never bothered with any of this. I have always viewed it as one of nature’s methods of pruning. The cicadas are not eating the foliage. They’ve been sucking on the tree roots for 17 years. The damage occurs when they lay their eggs in branchlets the size of a pencil. When the eggs hatch and emerge, they leave behind a hole in the branchlet which then breaks off with the first strong wind to come along. You may want to protect a very young tree with netting from May – mid-June, but I have never bothered even with this. If anyone has lost a tree or shrub due to the 17-year cicadas, please write in to let me know.
If you are like me, it’s hard to resist adding Hydrangeas to your landscape. Very few plants have such an outstanding show of blooms that persist for months. Even in their dried state, I find them an asset to the garden. In Maryland, we are fortunate to have so many options. But, when and how to prune? For this entry, I combined my experience with that of some expert landscape managers – Ron Ammon in Anne Arundel County and John Stevener in Baltimore County. I even consulted Dr. Francis Gouin’s book, Enough Said! This won’t be all of the Hydrangeas that are out there, but these are the most popular.
Hydrangea anomola var. petiolaris / Climbing Hydrangea – bloom in spring It’s best to prune shortly after flowering in the spring, but this is such a tough plant that it can be pruned almost anytime. It can even handle significant hard pruning of several feet, and if done in the spring, you’ll find that the new growth will hide all of your cuts in no time.
Hydrangea arborescens ‘Annabelle’ / Annabelle Hydrangea – bloom in spring
Cut back to 12-18” in height in early-March. Also, remove any old, dead canes. Some folks remove small stems smaller than a pencil, but I’m lazy, and never worry about this. Cutting back in this manner encourages the production of the large flower heads we crave.
Hydrangea macrophylla / Bigleaf Hydrangea – bloom in summer
This group includes the Hortensia varieties (snowball), and Lacecap varieties that bloom on 2nd year wood. It also includes all of the ‘Endless Summer’ cultivars bred to bloom on 1st and 2nd year wood. As it turns out, the pruning is the same for all. Unfortunately, we have had several years lately when just about all of our flowering buds (apical buds) have been killed by a late freeze. When this is severe, the plant could die back to the ground and need to start all over again. Those blooming only on 2nd year wood are likely to be without flowers for the entire season, while those blooming on 1st and 2nd year wood may have nice flowers in late summer.
The best we can do is to cut back after the last freeze when we can see which buds are still healthy and plump. Prune back to the height of healthy buds. Remember that this plant will generally grow 2-3 ft in a season. All old, dead canes should be removed. Dr. Gouin also recommends, “that last year’s flowering canes should be removed as well as canes thinner than a pencil in diameter. To obtain maximum flower size with stems that are strong enough to support the flowers, thin the remaining stems so the space between them is 3” to 4” apart. This will allow strong stems to develop and space for strong new stems to emerge.”
Hydrangea paniculata / Panicle Hydrangea – bloom summer/fall
Popular cultivars include ‘Grandiflora’ (PeeGee Hydrangea), ‘Limelight’, ‘Little Lime’(a dwarf form), ‘Vanilla Strawberry’, ‘Tardiva’ just to name a few. They seem to come out with new cultivars every year.
Hard prune in the spring. March or April will be fine. If you are concerned that a heavy snow might break a drooping branch in a bad location, then by all means, cut this back a bit prior to the first snow. It is possible to hard prune these plants in the fall, but then you lose the graceful architecture for the winter months.
Hydrangea quercifolia / Oakleaf Hydrangea – bloom late spring
The best time to prune is right after flowering, probably mid-late June. Unfortunately, by doing so, you will cut off many of the flowers you normally enjoy as they age from white to pink to mauve to tissue paper brown. Since this plant blooms on the previous years growth, pruning right after flowering is really the best option. If you prune in March prior to bloom time, the plant will do well, but you won’t have many flowers.
Cut the spent blooms back to a large healthy pair of buds. To reduce size, cut back no more than a third of the plant at a time. Do not cut back all branches by a third. Blooms appear at the tips of branches so an overall trim will just repeat the pruning errors of the previous year. Cut out no more than a third of the entire branches, if you want some blooms next year. If lightly pruned in winter or early spring, you will decrease the bloom count but may get larger blooms.
IF YOU NEED HELP
It’s not too late to contact a landscape contractor to help with the spring cleanup. A thorough cleanup, new spade cut bed edges and a fresh layer of mulch greatly improve the ease of garden maintenance throughout the growing months. Be careful not to smother newly emerging bulbs and perennials. If you have a lot of perennials in your garden, postpone mulching until after the foliage has emerged.
IF YOU HAVE A QUESTION…
about a particular shrub or perennial in your garden, please feel free to send me an e-mail. I will respond promptly. If you don’t remember the name of the plant, send me some photos.
Snapshot DG was recommended to me by a few individuals, but when I finally started reading the fine print, I became concerned. This product is pretty effective in preventing weed seeds from germinating. Unfortunately, it is reasonable to expect that it will be effective preventing seeds from my perennials from germinating as well. Then, I found… “Note: Injury on the following plant species has been observed following applications of Snapshot DG and use is not recommended.” Unfortunately, a number of my perennials were on this list. As a result, I will be eliminating its use in my garden.
Please use caution when working with this product, and I hope this information arrives in time.