New Cedar Hedge - When and How to Trim???

[Dirk Puslich]

Hello,

A month ago I had a cedar hedge planted in my backyard. They are about 6.5 to 7 feet in height right now but are kind of scrawny.

Over the years I want them to first bush out more, then grow higher.

I was told by a friend that when you trim the tops, it makes the new growth come out to the sides more and not get too woody, and nce they are bushy enough then you can let them grow higher.

I have 3 questions, assuming this is right:

1) What time of year should the tops of the cedars be lopped off (Fall? Spring? mid Summer?) Just once per year??

2) Given that they were just planted in mid September, should I wait a while before I take the hedge trimmers to them, so as not to stress them too much, or is it OK to trim them now?

3) Is there a rule of thumb as to how much to lop off the top? I was thinking about a foot off of each one for now.

- I live in Canada (Toronto) where we get some cold winters if that makes a difference.

Any advice would be appreciated! Thanks!

[Roger]

I would let them grow to plan height before top-pruning, which at that time will indeed encourage side growth. By then, they will be touching eachother, if you spaced them correctly. Early topping just after planting can stunt or distort vertical growth in a young hedge tree, and topping now may add shock/injury during winter. My understanding that evergreens can be trimmed any time of year, but live in a mild climate, so am not sure in your case. If plants were container grown there is no need to trim now, unless there was root damage in transplanting, in which case some overall trimming can reduce shock due to undersized root system.. Frequent minor shaping is what to go for. You will get an even and luxuriant growth that way. We trim our Cypress hedges 3 or 4 times during the growing season, the last trimming about now. Since there is no growth from Sept to April/May in your area, why trim in winter? Given that these are just put out, be sure to limit frost by mulching well with 4-8 inches of shredded bark or bark mulch, or hay. Don't forget to water periodically during thaws, if there is insufficient snow cover this winter.

[Rob Gray]

Do you know the exact species of tree that you have? A lot of people in eastern north america call the native Juniper trees "Red Cedar" even though they are not true cedards. The exact tree you have would affect the advice regarding puning.

Rob NE PA

Dirk Puslich wrote:

[Peter H]

You can prune these shrubs at any time of year. Trimming a foot off at this point wouldn't be a problem and there is no need to wait. Most shrubs would not want to be trimmed now as this would stimulate new growth which wouldn't have a chance to "harden off" before winter. The cedars won't care though. Long term you will probably want to trim them twice per year to keep them looking well maintained.

The most important thing to consider is to make sure that the root system has lots of water in it at freeze-up. As a general rule cedars like it wet all year round.

Peter H

[Renee Burry]

Hi Dirk, I recomend that you go to the library and get a book called, The Pruning Book by Lee Reich, put out by TheTaunton Press, ISBN 1-56158-160-7. Another book worth looking up is, Better Homes and Gardens the New Complete Guide To Gardening, ISBN 0-696-02573-6. Both these books deal with the pruning of coniferous & deciduous trees and shrubs. I have found both these books very usefull over the years, they also deal with many other garden problems. If your still unsure on what to do, visit your local tree & shrub nursery. There are many of them in Toronto who have horticulturist on staff and are willing to help. Several that come to mind are Sheridan, Mori, White Rose & Pickering. These places all have pros on staff, so pose your questions to them. Good Luck with it. Renee B. NF. Canada

[Winter]

Right, they naturally grow in swamps so they like lots of water.

If I had just planted a row of them I would probably be more concerned about making sure that they are mulched at the base for the first year to help them with the winter freezing and then to hold the water better in the summer. After that they are not that fussy. Most of them will do okay if you do nothing but if you have a whole row and dont take a little extra care the first year one or more may get a lot die-back but still live. That will stagger their growth for a couple years and make them look wimpy compared to the others. So, I still think extra care to mulch the first year is worth it. Maybe it is just the Maine climate/ ice age.

Similarly, I planted a row of privet for a hedge. They take a couple years to establish and then you spend all your time cutting them down after that. Because they require so little care in the long run it is easy to forget that that in northern areas they can get wacked down by the winter if you dont hold their hand a little the first year. I had a couple die back to the ground and then throw up new growth so I never replaced them but when you only have three months of growing season a year it really gets you out of sync if that happens.

Also, more than other evergreens, those cedars will brown out on you in the winter and then recover their color in the spring. Its just the way they are. Doesnt mean they are dying or anything, in case you are not familiar with them.

Dennis

[Dirk Puslich]

Thanks for your help everyone.