Sunday, January 26, 2014

Surviving Winter

Winter Solitude

Loneliness expresses the pain of being alone 
and solitude expresses the glory of being alone. 
-Paul Tillich

We had a mid-week temperature of minus 22F in the morning and the plants are protecting themselves. At least we weren't as cold as Watertown, New York - they were minus 37F on January 22, 2014. They were coldest city for that day in the lower 48 States: Watertown's Wild Winter. We're about 25 miles south of Watertown.  If you missed my blog post on the ice storm in the Watertown area  before Christmas you can check it out here: Welcoming in 2014!

Do you recognize this shrub? It is a rhododendron. It almost looks like it's dying with the leaves all curled up like that. In winter when the temperatures drop below freezing, certain shrubs protect themselves by curling their leaves in to reduce the surface area that is exposed to the cold. This also makes a more humid area inside the leaf. Rhododendrons that are grown in the shade usually have a larger and longer leaf to gather more light and if they are grown in the sun the leaves are somewhat smaller and thicker to retain moisture.

Here is your word for the day: Thermonasty. As a matter of fact I knew there was a word for this occurrence of the leaves curling inward to protect the plant, but I couldn't remember the term so I had to look it up online. Basically it means the response to a change of temperature. If you are interested in additional scientific information on thermonasty you can click on the link:

Temperatures below freezing (32F degrees) and this is what
the leaves will look like on a rhododendron.
I always know how cold it is outside before I look at the thermometer by just looking at the leaves on the rhododendron. If they're curled up - it's pretty cold out there and below freezing.

This is the same rhododendron in winter as in above two photos but temperatures above freezing (32F degrees).

Same rhododendron in early June (leaves are fully extended)
Frosts: Frost can be very damaging to some plants especially if you get a warm spell in late winter and the buds on trees start to open and then you get a heavy frost after that. You might not notice the damage right away and it may take several months before it shows up. You can identify frost damage from new growth that has pale brown patches and scorching between the veins on the leaves; evergreen needles can appear scorched and turn brown; a spring frost can damage flower blossoms and young fruit; and some plants appear to be water-soaked which turns dark green and in time turns to black.

If you planted shrubs and perennials that were recommended for your hardiness zone (USDA Plant Hardiness Zones) you should not experience much damage from the cold temperatures to your plants. But that's not always the case. Sometimes winter-kill also occurs.

Winter-kill: Sometimes a tree, shrub or perennial might be damaged by winter-kill. This can happen in the fall when the temperatures drop too fast early in the season and the plant has not acclimated to the colder temperatures. It can also occur during winter dormancy, or in or in the spring after the plant is coming out of dormancy.

It's possible that your plant was already stressed from last year's growing season if it was a particularly dry season. In winter when it's very cold, if the ground is frozen the plant can not take up water and the leaves will dry out and turn brown. Add wind to the problem and that can cause major problems for your trees and shrubs. In our area of New York we are fortunate in that we usually have significant snowfall which helps to protect and insulate our plantings. Where there is no snow on the ground and you have very cold temperatures your plants are more susceptible to winter-kill.

A very old trumpet vine
Another term used during this period is desiccation. Winter desiccation occurs when the amount of water lost in the foliage (wind being a contributor)  is greater than the amount of water taken up by the roots. This is more common with the evergreen trees. A lot of times the trees will look fine in the winter-spring but a few months later will turn brown. The top is more often to turn brown first because it is farther away from the roots and the least likely to have protection from snow cover. Newly planted evergreens might experience some loss of needles but should survive if they were watered well in the fall. If you have a dry season it's important to keep all your trees and shrubs watered through the fall to help keep them from drying out during the winter period.

Clematis vine on small trellis

In late winter or early spring when you are able to get back out into your garden, check your plants to see if the frost has heaved any of your perennials out of the ground. I've had this happen to irises and heuchera (coral bells), and other perennials. If you find that this has happened to some of your plants put a rock on them to keep them from getting further pushed out of the ground until you can re-plant them deeper into the soil.

If you notice that a plant is not growing in spring and you suspect damage from winter, do not dig it up right away or discard it. Sometimes it takes a few months for them to rejuvenate and start growing again.

Rugosa Rose hips in winter.
Perennials/Plants for Winter Interest: Some plants that you might like to add to your garden this upcoming year for winter interest could be the Rugosa Rose bush. This is a large shrub and it can grow up to 8' high. It has good fall color and produces hips after flowering. The hips will last all year (if the birds don't eat them). They are very tolerant of cold temperatures, and mostly pest free.

Be careful handling the shrub because the stems have thorns growing up all the stems. The thorns are close together and can be brutal. Plant it in an area away from foot traffic. I really love this rose because it reminds me of the old-fashioned roses with it's strong scented flowers. Not all of them are scented and its also is available in other colors. It is cold hardy for zones 3-9.

Rugosa Rose in summer

Tall Sedum (Autumn Joy)  photo taken October 2013
Another plant for winter interest is the tall sedums and specifically Autumn Joy. Depending on how much snow cover you get you can enjoy this plant from spring through winter. It is a very adaptable plant and will grow in full sun or some shade. It grows into a clump and is not invasive. It flowers from August and the flowers last through November. It will grow about two feet tall. The flowers open a light pink and turn very dark later on in the season. It also is a butterfly magnet. This plant is very easy to propagate as well. All you have to do is break a branch off it and plant it directly in your soil or pot it up.

Note: Ted (my husband) is keeping busy this winter. Second New Birdhouse!!! If you didn't get a chance to read my last post on birdhouses here is the link for it: Birdhouses - Think Spring!

Feel free to leave a comment. . .I would love to hear from you!


  1. Love the birdhouses Sue.....what an instructional post and I find I have less winter kill if the snow stays for most of the winter.

    1. Thanks, Donna. I'm glad you liked it. And I agree with you, the longer our snow lasts the less damage due to winter kill we have.

  2. We have had snow cover for the past several weeks with the severe cold which is a good thing, and even better there hasn't been ice on the branches...something I am thankful for. There was one winter a couple of years back that we had a lot of ice like you are and there were a lot of drooping branches on my evergreens that took a while to spring back with the help of arbor tie. I feel for your poor rhododendrons. Hopefully it will warm up for you soon so they will spring back. This was an informative post and as you can see I enjoyed reading it!

    1. Ice can be devastating to any garden especially ones with beautiful trees and shrubs like you have . You were fortunate that your drooping branches on your evergreens trees came back. Some times they never do and just continue to grow that way. We usually get a few thaws where it warms up here (above freezing). I don't mind that as long as it doesn't melt all our snow because the snow does insulate the plants. Thanks for your comments Lee.

  3. We too have been under snow almost the whole winter, but the boxwood still bronzed from the blistering wind. Always a challenge to see what plants make it through a tough winter. I have clients that have Rhododendron that looks like that each winter and they come back like nothing was drying to them. They would have been better off with different varieties though.

    1. We have a lot of pine trees in our yard that produces a great wind barrier for our plants and shrubs. I really think it helps protect them from our predominately west winds. But the pine trees also provide quite a bit of shade in summer so that cuts down on the amount of sun-loving perennials that we can grow or I should say grow successfully. The Rhododendron pictured above is about 20 years old and I've been lucky that it's been very hardy. I wish I would have recorded the name of it so I could publish it here, but that was before I started keeping records of my plants. Thanks for commenting.