Hedges

Any Questions?

Hedges and pruning Hedging plants fast growing hedges
Q. How do I go about cutting my laurel hedge with the aim to achieve a dense high hedge?	Q. How do I make my rather sparse beech hedge thicker?
Q. Can I cut back a lleylandii tree half matured to make a hedge, and what time of year is best?	Q. Are there any climbing plants which will grow through a privet hedge and will withstand the usual clipping?
Q. I have a beech hedge approx 8ft high. What is the best time to prune it back	Q. I just bought 15 Leyland Cypress trees and am debating about their spacing and distance from the fence
Q. I'd really appreciate any info you might have re a dieback problem I'm having with my laurel hedge.	Q. Information on 'Layering' a hedge.
Q. A few months ago my neighbor planted eight lleylandii conifers against the other side of my 6ft fence panels	Q. We have a Privet Hedge.... Early spring after the spring growth had appeared, 2 plants curled up & died.
Q. My neighbors Leylandii is now 15ft high and growing about 3 ft a year!	Q. I planted a hedge of 25 Thuja conifers in late September,.......The trees appeared to be doing fine until about a week ago

Q. I have a large west facing garden to the side of my Suffolk Cottage, bounding against a road. In April this year I planted a Laurel hedge along this boundary, I hope to eventually have a dense informal hedge around 6-8 feet high. The Laurels were 4ft high when planted and they have grown strongly over the summer, they are now around 5-6ft but are starting to look a little leggy. How do I go about cutting the hedge with the aim to achieve a dense high hedge? I very much hope you can help with this question as I have hunted high and low on the WW web and found very little advice.

A. If left to their own devices with lots of space, laurels will grow into a bushy tree / tall shrub about 20ft + high. It seems that this is what yours are in the process of doing, particularly as you say they have grown strongly. To get them to bush out, particularly low down, you need to prune quite hard.

Cut them back at the top to prevent the development of a strong leader which will encourage a tree-like form. It's difficult to guess without seeing them, but I'd take about a foot off. Laurels respond well if rather slowly to being cut back hard. If there are any branches low down, then cut them back close to the trunk - even though this seems the wrong thing to do. The plant will respond by breaking several buds where there were originally only one or two, so helping cover up the lower part of the stem. The best time to do this is late spring after they have flowered, don't expect to see much coverage for about a year, but it will come. If you're a bit unsure about this drastic action, just do a couple in the middle of the hedge (i.e. with one either side, and then the rest when you're confident it works (!)).

Prune laurels with secateurs and loppers, hedge shears cut the large leaves causing die-off at the leaf edge which looks a mess.

Q. Can I cut back a lleylandii tree half matured to make a hedge, and what time of year is best?

A. It depends on how big the tree is and how far back you want to cut it. Lleylandii like many other conifers have green leaves on the outside only, once you cut back any distance into it, you just have brown branches. If the tree is quite large it is unlikely to grow green shoots again from the brown wood. I have seen it happen, but it took about three years from being cut, during which time the hedge was an ugly bare brown.

Conifers that have been grown as trees usually respond to drastic cutting back by dying. You could always plant a laurel in its place and then train that as a hedging plant. Laurels have the advantage that they will respond to drastic cutting back by growing new green leaves from the bare brown wood.

If you want to have a go at it, I'd do it in late spring / early summer.

Q. I have a beech hedge approx 8ft high. What is the best time to prune it back and do you advocate the method of cutting back on one side the first year, and then cut back the other side the following year. I also want to reduce the height, what is you advice on going about this task?

A. It depends on how drastically you wish to cut the hedge back. For general maintenance of a beech hedge, two trims a year are fine, once in midsummer and once when dormant during the winter months.

If the hedge is very overgrown then any major pruning should take place in midwinter. Leave it until then if you want to take more than about 2 feet off the height of the hedge involving cutting back into larger established branches.

The cutting one side at a time approach is only necessary for drastic pruning. If you want to reduce the width by cutting into large established branches, then do opposite sides on alternate years. If the cutting back only involves young twiggy growth, then it's not really necessary.

Q. I'd really appreciate any info you might have re a dieback problem I'm having with my laurel hedge. About 2 months ago a three feet wide section of the hedge appeared frost-damaged - we had 2 or 3 very sharp drops in temp at night during the previous week. The hedge had been well cut back c3 years ago due to building work but was flourishing with lots of lush new growth - I thought its thinning perhaps had made it susceptible to frost damage.

This 3 feet section however has now extended to almost 6 feet wide & appears to be spreading. My neighbor & I are very concerned & would appreciate any advice on how we might save it.

The laurel is c.12 feet high/50 feet long & I think was planted when the houses were built in 1920s - the leaves are fine and small and a light green color, not dark. The dieback appears to start from the bottom up with leaves wilting, then brown spots, then entire leaf brown and stems browning. Is there a disease that affects laurel? or could the roots be water-logged (nurseries here have been recently selling off plants due to the extraordinary wet weather we have had!) A friend has also suggested cats & their 'ablutions' (another neighbor has two new cats).

A. If those cats can kill off a 12ft high by 6ft wide 80 year old laurel, I'm glad they're in Northern Ireland and not over here! Seriously though I think we can disregard the cats as a factor.

It's difficult to tell without seeing the hedge directly. With such a large old plant, I think the most likely cause will be a fungal disease triggered by several factors that have acted together to weaken the plant. Age, water logging, physical damage - letting fungal spores in - will all have a part to play.

The first thing I would do would be to delve into the hedge and determine how many plants the die-back is affecting, is it just one or is it moving to others? Look carefully at the plants, leaves, stems, trunk for any clues, I presume there aren't any pests or you'd have mentioned them? Are there signs of fungal disease any where? especially low down near the ground, is the bark damaged? Is there anything peculiar about where the damaged plant/s are growing?

Are the branches the dead leaves are attached to dieing too? Snap one or two and see if there are signs of life. If they are dead then cut back into a live part. If they are still alive, things are looking better.

To be honest things don't sound too great and it may be a question of containment if the problem can't be dealt with directly, stopping it from spreading to the next plants on in the hedge. If the problem is containable and stoppable then the good news is that laurels usually recover well from some hard pruning.

Q. Hi. I have spent years developing my little garden into what is now a very enjoyable and functional environment. A few months ago my neighbor planted eight lleylandii conifers against the other side of my 6ft fence panels. I am very worried about the speed at which they have grown (8ft now) , and about their ultimate potential to take the light (and views) from my hard-earned garden. I get on well with my neighbors, but do not want to risk causing any bad feelings about this situation. Is there any legal requirement for the guardians of these amazing trees to keep them within a specific height (in a small garden) ? I also use my garden for amateur astronomy, and the lleylandii will eventually make that impossible. Is there a neighborly way of sorting this matter, avoiding the common "neighbors from Hell" saga which ruins so many friendly neighborhoods?

A. The answer at the moment as far as I'm aware is that legally there is nothing you can do. There has been a lot of publicity about this problem in recent years and there are moves afoot to pass a law along the lines of those that apply to planning permission for buildings that may deny neighbors "light and air", though it's still early days.

Your answer probably lies in that you get on well with your neighbors. Most people plant a hedge in front of a fence in order to hide the large expanse of wood and so once the hedge reaches the top of the fence the job is done, the problem comes when the owner of the hedge doesn't trim it regularly. This is not usually due to any malicious intention or even that they really want a 20ft high hedge, but more the effect of the casual neglect of a non-gardener on an active gardener next door.

Your only hope currently is to talk to your neighbor and explain your worry, he may not even be aware that you see it as a potential problem, and ask if he would keep the height down. Try explaining that cutting a little and often will make the hedge much more manageable, I'm sure one of the reasons that large Lleylandii hedges stay that way is that it's such an almighty task to chop off and dispose of 6ft height or more of dense conifers, so the owner just avoids it. It may even be worth your while suggesting that if he can't or won't cut the height down, would he mind if you did? You can't do this without permission as the hedge belongs to the neighbor, but it may a practical if less than ideal solution. I used to live in a house with large Lleylandii hedges on 3 sides of the garden, two belonged to me and one to a neighbor who never went near it. Eventually I ended up trimming all hedges to the same height with the neighbors "permission", yes it was galling! but it solved my problem.

Q. My neighbors Leylandii is now 15ft high and growing about 3 ft a year! I have asked him to cut this down to a reasonable height of about 6ft which he refuses. He actually pulled up trees under a TPO (tree preservation order) 6 years ago and planted these monstrous green things and now the view of the valley is totally ruined. What is the current legislation regarding this and if all else fails how do I kill them?

A. Despite promises of legislation, there is still no law about the height of a boundary hedge. Your best approach is probably to go to your local council and ask if there is anything they can do. If trees under a TPO were removed they can be made to be replanted as they were, was anything done at the time? I don't know how it would be considered so long after the event.

What you can do is to prune the roots where they encroach upon your land, i.e. dig down and cut them at the boundary, if this damages them, then so be it. Obviously though, this is hard work and not the best approach for a conciliatory outcome. As for killing them, this would be against the law, you are not allowed to poison them even where they encroach upon your land.

Q. My beech hedge is approximately five feet high and 25 yards long but it is very thin and sparse. How do I turn it into a thick hedge?

A. I would guess that your hedge has been allowed to grow upwards pretty much since it was planted and so the plants are trying to do what comes naturally i.e. grow like trees.

You need to stimulate it to produce more side shoots and bushy growth rather than going upwards. This is done by pruning to stimulate new growth.

Beech should be given only moderate pruning. Vigorous leaders and laterals should shortened by no more than one third of their length. Weaker growth can be cut by up to two thirds of its length. By the sounds of it this will take you some time to go down the full length of the hedge, I'd prioritise the leaders first and then go back and do the rest a bit at a time.

It would also be a good idea to fork in some fertilizer after the pruning, gromore or blood, fish and bone are good slow release fertilizers.

Q. Are there any climbing plants which will grow through a privet hedge and will withstand the usual clipping? Possibly a vigorous clematis or honeysuckle? I can't cut down my shared privet hedges but I desperately want to make them even the tiniest bit more attractive, especially as they have been cut back very hard this year as they'd been neglected in the past & look like twigs at the moment.

A. Some climbers such as those that you mention will withstand the regular cutting that your privet hedge will get if they grow through it, though I wouldn't do it myself. The plant will almost certainly never flower, or at least not as well as it would do otherwise. Whenever you cut the hedge/climber you'll be removing resources that could be put into flowering and possibly at some times of the year, the flower buds themselves.

Climbers growing through hedges only work in a very informal setting with maybe a single annual cut, situation where privet aren't really planted.

The good news on the other hand is that privet recovers very well and very quickly from a severe cutting into bare wood. Your hedge should be all bright and green again in much less than the time it would take for a climber no matter how vigorous to establish.

Q. I just bought 15 Leyland Cypress trees and am debating about their spacing and distance from the fence (chain link). I realize that the most commonly recommended distance between trees is around 80cm., however I have all too often seen conifer hedges choking each other (apparently) from too-close spacing and/or being too close to the fence. Since a Leyland Cypress can supposedly grow to 3 or 4 meters wide, would there be a problem spacing them at 150 centimeters rather than 80?(How much longer will it take to form a dense closure?) Thanks Very Much! (from Spain).

A. The recommended spacing is to achieve a good dense barrier fairly quickly while giving each tree an adequate amount of space (they might look "choked" but they're fine for a hedge). The main reason for choosing Lleylandii is for their growth rate. It's difficult to give a time scale of how long it would take to form a good hedge at 150cm spacing other than about twice as long as it would at 80cm, local growth conditions vary enormously and I'm not even going to guess how quick they'd grow in Spain!.

I'm not keen on the use of Lleylandii and my own approach would be that if you are prepared to wait longer for the hedge to form, then why not use a more attractive and less bullying hedging plant instead (at the recommended spacings).

Q. I am wondering if you would be able to give me information on 'Layering' a hedge. I remember as a child having layered hedges around us. We lived in the New Forest. Now having a small property in Victoria, Australia, I would like to create a layered hedge using Australian natives. I would appreciate any information could give me. This craft is not practiced here, so information is not available. Thank you in anticipation

A. Sorry I can't help directly here. Unfortunately hedge laying is a dying art, it is also one of the most skilled of old countryside crafts so brief advice wouldn't be of any use.

You could try contacting "BTCV" British Trust for Conservation Volunteers or the UK National Trust, I don't know the addresses but a www.google.com search should find them easily enough. I know that the BTCV in particular used to produce some very detailed publications on all kinds of countryside crafts that may give you the information that you need.

Q. We have a Privet Hedge, approx 7 ft by 2-3 ft. Unsure of it's age. Early spring after the spring growth had appeared, 2 plants curled up & died. They had lost most of their leaves the previous autumn, however when they sprouted in the spring we thought all was OK. We had cleared all the ivy from around the base of the plants the year B4 & thought maybe this had had some effect. Now it seems that part of 2 other hedges are also starting 2 die. They are not anywhere near the 2 plants that died in the spring. Somebody suggested it was because of a lack of water over the summer, however one of the hedges is situated behind our herb garden and so was watered regularly during the summer. The leaves now are a mix of dark purple / red and yellow / brown. Some of the plants show some new green growth, others don't. They appear to have thinned out quite considerably too as we can now see through to the other side. Some of the old wood has a green soft coating to it, like a thin moss.

Also a few months back I noticed some of the leaves had curled up on themselves and turned black, with further investigation I found a small cream colored larva (3mm) inside the leaf walls surrounded by what seemed to be digested black remains of the inside of the leaf. I have not been able to find help anywhere on what this might be. It doesn't leave tunnels like a leaf miner, rather it just seems to eat everything in between the 2 walls.

Please I don't know what to do next. I feel we are in danger of losing all the hedge. It was last pruned late spring / early summer and we've been afraid to touch it since then. I have noticed a few other hedges in the district looking somewhat the same, but there are others which look fantastic. Is it worth putting down some Sequestered Iron or spraying with a fungicide?

A. I think the leaf miners you found are incidental rather than the cause of the problem, they are not uncommon on privet. It sounds like either honey fungus or wilt (a wonderfully vague term), both are fungal diseases that will readily attack privet and cause the symptoms you describe and over the time scale you describe. If it is honey fungus, you should be able to find some of the bracket-like fruiting bodies on the trunks of the plants. Wilt is caused by one of a group of fungi that give no outward signs other than the symptoms of the plant that is suffering.

In either case there is little you can really do directly. Cut out all of the dead wood and stems and burn them, clean pruning tools carefully afterwards so not to spread spores. Clear under the plants of weeds, ivy, dead leaves and any other debris and give the hedge a top-dressing of fish blood and bone meal lightly forked in to help build up the strength. I have to say though that the outlook is not very positive, particularly as you say other hedges in the area are affected, it seems like the disease is endemic and may re-infect.

Try my suggestions, but be aware that you may eventually have to replace the hedge with something that has resistance to the disease that is affecting it.

Q. I planted a hedge of 25 Thuja conifers in late September, 20 inches apart in a well-prepared trench. The trees run in a North-South direction for approx. 40 ft. and there is a 6 ft. fence to the Western side.

The trees appeared to be doing fine until about a week ago, during recent heavy rains in the UK. On 5-10 trees there are a number of brown leaves, especially nearer the ground that are falling off. I can accept that there may be some loss over the winter. However, some leaves and stems higher on the plants in random locations are turning an almost blue-black color and falling off. Is this normal, or do I need to take action?

Thanks for your question. It's not always easy to work out what's happening when conifers start dying off. I wouldn't expect the browning off or blackening of stems at all, neither are expected responses for newly planted conifers in such a short time.

A. I think the strongest possibility is an infestation of Phytophthora fungus. The fungus thrives in damp and waterlogged soils so may be in your soil, but the speed at which your plants have been affected implies that there is a good chance that they arrived with it. It kills the plants from the roots upwards and can give the blue/black color on the stems that you describe. The roots of affected plants are reddish brown or black rather than white.

To quote from the MAFF website:

Some trees, such as Lawson's cypress are highly susceptible to Phytophthora root rot. Nevertheless, root rot is almost always the result of over-watering, root damage or prior drought stress, poor soil conditions, flooding, etc. Pythium and Phytophthora can almost always be found in dead, rotted roots, so may not be the primary cause. Except for highly susceptible species, re-planting with healthy trees should not be a problem if the soil and environment are improved and good horticultural practices are followed

Other possibilities - you'll need to investigate a bit further:

Conifers have a delayed reaction to stress and damage that is more immediate in broad-leaved plants. They may have been damaged or dried out before you got them and then showed signs later. A couple of years ago I bought 6 "bargain" conifers at an auction that looked very healthy, took them home and watched them turn brown and die over the next two weeks. They had been totally dried out in their containers and then watered just before I bought them.

Dog urine. Quite high on the list of possibilities from the symptoms. Is it possible that a dog/s are spraying on the hedge? The affected areas have a greasy appearance if this is the problem.

Are they being water-logged at all? Try digging down near the roots to about 6-12" is the soil boggy?

Drying out after planting could be a possibility if unlikely. If they are in a wind-swept place though and weren't watered in initially or during a dry spell it may have caused the damage you describe.

Cure? obviously depends on the cause. If it's Phytophthora there's nothing you can really do. I'd go back to where you bought the plants from, but there's no chemical control available to cure it. The fungus remains in the soil so despite what MAFF say, I wouldn't risk planting the same again. Tsuga heterophylla (Western hemlock - not keen on exposed windy sites) and the ubiquitous Lleylandii (tough as old boots and grows like mad) are resistant.

Hedging plants fast growing hedges