Abscission

004
The leaves of trees and woody plants are solar cells that convert the energy from the sun into food that enables a plant to grow and sustain itself.  This is a gardener talking-not a botanist.  I observe that once a leaf is no longer able to perform its job, that leaf is shed from the plant.  The fall is a very long process of abscission beginning in August, and ending once winter comes.  Hellebores do not truly part company with their leaves until the spring following.  Once the flower stalks push forth and bloom, then the hellebore concentrates its energy on new leaves.  The leaves from last year pictured above-I am surprised they look as good as they do, considering this past winter. I will cut last years leaves off soon, so as not to disturb the flower stalks about to emerge.  Hellebore foliage cares not one whit for abscission.  They hold their leaves until the new season’s flowers are up and representing.

014The mechanism by which deciduous plants shed their leaves is complex, and very interesting.  Anything a plant no longer needs to survive, it sheds.  Linden trees in water stress will shed their interior leaves in order to preserve the health of the tree.  Yellow leaves on the interior of a deciduous tree could mean it is in stress from a lack of water.  Fewer leaves needing water may help in a drought.  Any tree needing water will shed any leaves it needs to, to preserve its life.  The life central of a tree may direct that tree to shed unnecessary leaves.    An evergreen tree in great and life threatening stress from environmental conditions may produce an incredible number of cones. Plants are engineered by nature to survive.  Survival marks and engineers all of life. Gardeners one and all enjoy the process of fall color, and the dropping of leaves.  Some trees, such as parrotia and beech, hang on to their leaves until the emergence of the new leaf buds in the spring push the previous years leaves off.  My parrotias are still full of leaves, albeit brown leaves.

013 I am not so anxious to remove the leaves and stalks from my perennials in the fall.  I like the look of the snow on the remains of the garden.   I also believe this detritus helps to shield and cushion my plants from fierce winter weather.  I am content to let the garden go down in the fall, with every stalk and stem intact.  I only do a spring cleanup.  In the fall, every plant is shedding and covering its own.  I don’t see the need to disturb that.  Winter is a tough season.  Our past winter was brutally cold and snowy.  I am glad I left the garden be this past fall.  The European ginger under this bench is virtually evergreen.  It hangs on to its leaves with a vengeance.  I never remove the old leaves; I leave them be.  What I leave be in the garden eventually becomes compost.  If you ever have the urge to clean up every leaf in the fall, think about the forest floor.  The forest floor is a healthy and vibrant environment-just what you would want for your garden.

011None of my roses shed their leaves this past fall.  The leaves survived a terribly cold snowy and windy winter, intact. The leaves are still hanging on, this first week of April.  We have only had temperatures above freezing for a few days.  I cannot tell yet if my roses survived this winter.

008The leaves still attached to the roses-I have no idea what this means. I have seen lots of deciduous shrubs with the fall leaves still intact from last fall. Did the winter come to us so quickly that the process of the leaf drop was interrupted, detained?

007Though nature can throw a mean and deadly curve ball when I am least expecting it, I know this spring could be just as tough as the winter we just experienced.  I sat in the rose garden tonight for the first time since last October.  Yes, I had on my hat and coat.  I have no idea what is to come.

012Should you have any idea why my roses never shed their leaves last fall, would you write me, please?  I have never seen this.  I do not know what to make of it.  I am prepared for the worst.  I am a gardener, first and foremost.  Dealing with the worst in a garden is ordinary.  Dealing with an unknown worst-keep me company, please.

Comments

  1. Janice Casper says:

    I’m glad to hear about the leaves on your roses. The first day I examined my yard I found leaves on my Aloha rose and had never seen this before. Funny the chestnut tree, which usually keeps it leaves most of the winter, lost it’s leaves early winter. First hellebore bloom this morning. Wahoo!

  2. You know, I was amazed that most of my roses didn’t drop their leaves, either. We here in CT had an early cold blast last fall. We’ll soon see if they all made it out alive.

  3. We are worried about roses here in central Wisconsin as well. Some of the smaller branches closer to the ground have a green sheen to them which to me says alive. I like to cut back my shrub roses by at least a third before they start their new growth and then watch carefully to see from where the growing begins and trim them off within a half inch of that later on, leaving only 3-5 of the larger canes. This week when I took off that top third, I don’t think I cut into anything alive; not usually the case.

    My climbers I do a bit of thinning out of anything noticeably dead and maybe take off the straggly longer tips, but it is pretty much always a wait and see sort of thing. We have so few climbers which actually survive here (Canadian Explorers, Blaze, and Eden). This year they, too, held their leaves; but I think that is typical here. We had a very long string of days (maybe 60?) where temps did not reach freezing and nearly 50 days in a role with sub-zero temps at night.

    Very few roses survive here. Recently our zone had been “upgraded” to 5b, although when I was growing up it was 4a. I think this year it seemed closer to 3a (Minneapolis). There are a scant few roses which survive there. I think it sometimes comes down to snow cover and hydration at the time the ground freezes. I always keep watering my roses when I can until the ground freezes.

  4. Early frost or extreme cold often “kills” the abscission process. The marcescent leaves, smaller leaves on on deciduous trees, sometimes stay on lower branches, or throughout smaller trees and shrubs. I don’t think why can be answered w/ certainty. I’ve read it’s some type of survival technique, possibly keeping new Spring forming buds protected from Winter temps, or on smaller shrubs, ( roses ), keeping wildlife at bay. Leaves work as a deterrent for deer.

  5. My roses did not shed their leaves this year. Perhaps the mild fall and early winter slowed the arrival of the dormant season. Then winter hit fast and hard. The leaves stayed with the plant. I pruned two weeks ago and welcomed the new growth that is pushing out this past weekend!

    Even more amazing – the hardy kiwi’s survived the bitter cold!

  6. my aloha roses sometimes do this. they’re usually among the last to shed their leaves. i used my google-mom prowess and found an article about maples that don’t drop their leaves when they should. it could be a similar reason for roses: they’re caught short during an early winter.

    http://ravallirepublic.com/lifestyles/home-and-garden/article_3a25ddfc-c40e-11e2-a991-001a4bcf887a.html

  7. I’m interested to read the responses here. In my current garden I have one lone hybrid tea that was only planted last May. She maintained every single leaf as well through the winter. I haven’t grown roses in a few years, but I hadn’t ever remembered such an occurrence. Earlier this week I noticed the same thing in a friend’s established rose garden. Crossing my fingers! Very happy news to share-in one of your posts on peonies, I mentioned that I was nervous the 60 year old peonies I was given in November might not have survived the brutal winter. Each one is sprouting and looking vividly alive!

  8. Starr Foster says:

    Your roses look great. Mitch is our rose expert and he said they should be fine, especially since they were under a lot of snow most of the winter – were they not? Also yours are big roses, not hybrid teas, and are grown in a warm, protected part of your garden so they are likely to come back with great vigor. You could cut the tip of a shoot, or scratch the bark off a little spot to see if it’s still green. I wait till May to prune off winter dieback, because a cold snap before then can kill the stem back even more.

    Mitch’s hybrid teas dropped their leaves even though they were under a huge drift of snow all winter, and he is expecting them to be very happy because of the snow.

  9. deb myrick says:

    Here in Northern California, our roses rarely shed their leave and come February I go out and pull the leaves off. I believe your roses will survive.

  10. In PA, the hellebores are already up and the flowers are out. some are farther along than others. Even though we had a rough winter here, also, we are a little ahead of the Detroit area. I cut off my old leaves about two weeks ago. It makes me happy to see them up and blooming.

  11. This was my first week out in the garden post winter. Surveying the damage and, like you, wondering what has survived. I celebrate every spring. But between the 2012 drought and the 2013-14 winter, this year’s growing season will be a true celebration.

  12. Priscilla says:

    Is it possible that some of the plants didn’t get hardened off before the extreme cold came this winter? Did the leaves die while still on the branch?

    I carefully cleaned up my Hellebores and Epimediums today. The buds are about 3″ tall on the Hellebores and the old foliage was detracting from the plant. I am so excited to see some color in the garden.

    Thank you for sharing your plant knowledge with other gardeners.

  13. Carol Passavant says:

    I can’t help with your roses, mine dropped their leaves. I do want to thank you for the tip on hellebores, mine are beginning to sprout, but I didn’t know to keep my hands in my pockets until the new bloom is further along. You posted this just in time. Thank You.

Leave a Comment

*