Don't DO That 2002

Don't cut live branches off evergreen trees!

Get in you car, right now, and drive around your neighborhood. Between fifty and seventy percent of the pines, spruce, fir and other evergreen trees you see will have had lower branches cut off by homeowners. Perhaps you didn't even leave your driveway.

Never cut a healthy limb from an evergreen. I have never seen a tree treated thus that was not in some state of decline as a result. Cutting lower limbs off spruce is the worst offense. Spruce are designed so that the lowest branches, those that touch the ground, support the branches above, and so on, all the way to the tip of the tree.

We cut the branches off around the base – I don't know why, it's usually a guy thing, the man of the house needs to show the world he can grow grass under there – and when winter comes the snow load collapses the branches. No problem, the branches are designed to lock together for support. Except down at the base there's no branches, so the lowest branches are stressed or crack because they have nothing to lock down onto. Then in a year or two, those branches die.

Cutting healthy branches off a pine exposes the tree to insect and wind-born fungal disease. You're also cutting off the leaves – that's what the needles are, leaves in needle form – that the tree relies on for photosynthesis. Removing limbs with healthy needles is the same as you losing blood.

Oh, I know the big cause for it. It's the idiot who lived in your house twenty years ago. Planted a red pine six feet from the edge of your driveway, and you thought it was magnificent until its lower limbs grew so wide they started scratching the side of the Lexus. So we make the limbs go bye-bye.

What you should do is cut the tree down. That's right, the only time it's correct to prune an evergreen is when administering what we refer to in Renegade Gardening as, "The Ultimate Prune." Cut it down, plant an evergreen that is going to fit there in 30 or 40 years. Or cut it down because it's a dumb spot for a tree and don't plant another one. That red pine could have grown from seed, it served a purpose for awhile, but now it doesn't.

Clear out your spruce that have had all their branches cut off up to ten feet on the trunk. Look at them, they have dead branches you can no longer reach, they were planted too close together, now they're dying, and they look like hell. Replace them with an entirely different landscaping scheme, perhaps some pyramidal evergreens, and a collection of deciduous shrubs.

Be aware that spruce are presently having a tough go of it all across the country. Cytospora canker is a fungus wiping out Colorado spruce, but can infect all spruces, red and Eastern white pines, larch, fir and hemlock. The cankers release a resin that turns bluish-white on the bark of limbs. Needles turn yellow, then brown, and the limbs die, usually from the base up. Rhizosphaera needle cast is also a fungal disease, and is easy to diagnose – needles turn brown and drop, but only second year growth. New growth is green, such that branches looks dead except for green at the tips.

There is no treatment or cure (see "The Ultimate Prune," above) for either disease, with the exception of having a tree service spray for rhizosphaera needle cast, but only if you catch it right away. So the best way to avoid these problems is to maintain healthy, well-watered, fertilized, properly spaced trees. With all their branches.

Well, there I go, 616 words in fifteen minutes. Sorry it's so long, I didn't have time to make it shorter (Benjamin Franklin). Maybe next time.

Don't design straight lines into the landscape.

Nothing creates a boring landscape more surely than use of the straight line. Be it in the shape of our flowerbeds, the planting of flowers within them, or the planting of shrubs, thinking straight guarantees there will be no hope for magic.

Look at the shrub planting in the first picture. Lilacs, I think (though I can't be sure, I didn't even get out of the pickup to snap the shot). There's the start to an alluring landscape. OK, I understand that you are interested in creating a barrier between your spanky new home and the boulevard, but why let a straight road dictate what to do?

This hedgerow should curve, swoop, curl, and curtsy. It should let the road know, in no uncertain terms, that nature is taking over. I'm also well past the point of seeing why any proposed shrub barrier should be comprised of all the same plant. What are they using here, fourteen plants of the same variety? Why not five or six varieties of shrubs, a third to half of them evergreen shrubs? How in the world are we going to get any sparkling contrasts in textures, any flow, any mystery, with this farm windbreak? Just as important, what's going to provide winter interest?

Look at the second picture. There is way too much of this taking place across America. What is it about $400,000 homes that we can't build them without making it appear as if nature was scared away by all the hammering? Big brick castles that slam down to lawn once you get four feet away from the exterior walls represent the essence of poor landscape design.

Always, start at the start. What is it we love about nature? The third photo says it all: in nature, there are no straight lines. That's nature's big hook. Straight lines are a human invention, and when we head into the wilderness, the first thing we respond to is the utter lack of straight lines, right angles, and perfect circles.

Let your landscapes curve and rise and flow. The fourth picture shows what you can do to the side of your garage when one lets the laws of nature guide. The last picture is to prove that even when allowing for ample lawn, straight lines in the landscape need never enter the picture

Don't use rock as a ground cover around trees and shrubs.

Don't use rock as a ground cover around trees and shrubs.

Half-inch to two-inch rock – often touted under the name "decorative rock" – is the worst possible choice for covering the ground around plant material for a wide variety of reasons.

We first saw rock used in this manner in the '60s, and many homes across America can be dated by its use. It was an unfortunate trend, like orange shag carpeting. Except the orange shag carpeting was ripped out by the mid-70s. Decorative rock, unfortunately, remains in far too many American neighborhoods.

From a horticultural standpoint, it's deadly. Rock heats up, then retains the heat, frying the roots of the trees and shrubs it surrounds. Often, landscapers would lay down black plastic first, cut a hole in it, and plant the shrub. Now you're heating the roots, plus suffocating and killing off the soil under the plastic. Trees and shrubs mulched with rock never thrive. Those shrubs in the pictures have to be first-year plantings.

Try to rearrange a landscape that has been covered with rock, dig up a plant, move stuff, plant something new – there's no use even trying.

But by far the biggest problem with rock is that it looks like hell, particularly in the north. What are we trying to recreate here, Palm Springs? Tucson? It's such an unnatural, vile, '60s look. It makes our landscapes look so clinical, so artificial, so phony and laughable, like a drawing from the '40s of what a city will look like in the year 2000.

The classic is the tree – almost always a birch – sitting alone in the middle of a front yard, circled politely by black edging, the circle filled in with white rock. Please.

If you are unfortunate enough to purchase a home circled by "decorative" rock, your first order of business is to dig it all out and have it hauled away. Or rent a Rockvac. Then plant shrubs and other material that are going to fill in and look natural. Mulch the ground around the plants with shredded hardwood bark. Don't ever lay down black plastic first. Even a landscape fabric that lets water through will come back to haunt you in ten years. Use four to six inches of bark, and weeds won't be a problem.

Leave the decorative rock to neglected shrubbery surrounding gas stations, Wal-Marts, and fast-food restaurants. Peace, brother.

Don't circle trees with stuff.

I don't know where this practice started, the Midwest I suppose, perhaps Hopkins, or Edina. People see that tree out in their yard and they just can't leave well enough alone.

I imagine some think they are engaging in some form of landscaping, and in fact they are. Bad landscaping, landscaping that says, "This individual tree is thought of so little as being a part of any whole that I'm going to give it a silly, frilly little skirt to make it really stand out and look bad."

And people circle them with such amazing assortments of stuff! In Minnesota, circling with bricks left over from that patio job that went south is big, a single layer for the new gardener, maybe a triple layer for the assured do-it-yourselfer. Then there's that curved, reddish concrete edging that makes little tombstones all around your tree, that is sold to this day AND IS DESIGNED TO SERVE THIS PURPOSE, something I find astonishing.

Of course you'll see concrete retaining wall block used in this manner. Does it say anything about how ludicrous is this practice that even a tree circled with natural stone block, or field stone, also looks ridiculous?

The classic is the tree, usually a vastly mature oak, circled with hosta. I'm sorry I don't have a picture, the hosta weren't up when I was out shooting the photos, but you know what I mean. You have this majestic, seventy-foot oak, king of the forest, lord of all trees, forced to endure the indignity of wearing a circus clown's collar, a little girl's teeny tutu, I used to be something, I used to be grand, now look at me, look at me.

If a mature tree is growing from your lawn, let it grow straight out of the lawn. Grass looks great growing right up to the shoulder roots of a tree. If a newer planting, you'll want to circle it with shredded bark until a solid root system is established, then ditch the bark after five years. Best of all, make a tree a part of the landscape, the focal point of, well, a point, a swooping, jutting point of landscaping that starts at the house and extends out and around the tree.

If you're going to circle something, circle a date on your calendar when you will go out into your yard, and set your trees free.

Don't raise the soil level over tree roots.

New gardeners often don't realize how exacting are the requirements of tree roots. Most large trees have broad shoulder roots that cut deeply down into the earth to stabilize the tree, but subsist off the moisture and nutrients provided by the massive secondary and tertiary root system existing in a zone no deeper than six to eight inches from the surface. Why so shallow? Oxygen.

Roots need air. Some are real wimps, like the roots of the silver maple, that need so much oxygen they actually grow at and above the surface of the soil, where we nick them with our lawnmowers. The secondary feeder roots coming off these main roots are only a few inches deep. That's the way Maples like it.

Raise the level of the soil above these roots and you can kill the tree. Even changing elevation a few inches can stagger a tree (or shrub) and cause it a time out while it valiantly reroutes its feeder roots upward, in search of the proper root level. Home builders have been roundly chastised for saving mature trees around the lots they develop, then raising the soil level as they excavate such that the trees die later on. Even compaction of the soil around trees, caused by heavy equipment, can weaken and kill a tree. Why? Compaction squeezes the air out.

The homeowner who decided to install a five-foot berm surrounding two-thirds of the tree pictured has probably killed this tree. About a third of its root system remains where intended, but that may not be enough. The tree will receive quite a jolt this summer – try cutting your food and water intake by two-thirds, and see how you feel in a year. Thus stressed, the tree will become susceptible to disease, which will probably finish it off some years down the road.

Unless a formal hedge, don't control the height of deciduous shrubs by topping.

With most shrubs, it backfires. When dogwoods, viburnums, euonymus, cotoneaster, you name it, get too tall, the homeowner will often give the shrub, or hedge, a one-time haircut, right across the top ("topping") in a effort to reduce the height. Works for about twenty minutes.

Then the shrub responds by sending up five, six, eight new branches straight up from the tip of each branch that was pruned. The haircut activated a hundred dormant buds, and now that shrub is really ready to fly.

You wind up with old wood and decent stem form erupting with thick, tender wood that will quickly grow two to five times taller than the length of branches removed.

Looks like hell. The way to prune deciduous shrubs is to remove old wood at the base, no more than one-third of the oldest growth per year. You'll get new growth from the ground that will keep the shrub looking nice. But for most shrubs, you can't effectively control height.

In a formal hedge scenario where you are clipping and snipping four or five times a season, and the shrub has a relatively fine branching habit, such as a boxwood, you use the new growth to your advantage. You are constantly keeping it under control and letting the new growth provide lush foliage. It works with a viburnum hedge, or a dogwood hedge also, but the key difference is you are sharply pruning the tops (and sides) quite often during the season.

Do it once because the shrub(s) was getting a little taller than you liked, and you'll get far more than you bargained for.

Don't install plastic landscape edging improperly

Magnificent commercial installation: black plastic, pink rock, edging set too high

Improper connection resulting in heaving and mower damage

Total frost heave of homeowner installation: cheap edging, wrong side out, no stakes

Stomp your outward corners

Pound stakes at flat angle

Nearing completion: stakes in, corners stomped

Such a simple, helpful product, yet so easy to screw up.

First off, a few notes: some gardeners don't like to edge their beds with plastic edging, having found that when they want to expand or change a bed, well, there's the edging to deal with. Edging keeps lawn grass from invading the garden beds, but isn't necessary if you cut a narrow trough an inch or so deeper than the grass roots, all around your beds, and maintain it weekly. A nice, veddy English look, but one that requires fastidious maintenance.

I use plastic edging anytime I'm creating a bed that I trust is perfect the first time, and install a lot of it when I'm out doing residential garden installations. And man, do I see a lot of lousy homeowner AND professional installations. Here's what you need to know:

• Buy expensive, commercial-grade edging. The good stuff measures five-and-half inches wide, or more. That cheap, flimsy stuff sold at Menards and Home Depot is too susceptible to frost heave, especially the stuff that doesn't come with steel stakes. Landscape supply yards sell the good stuff – I use Ace of Diamond brand – and some home centers are now stocking a good commercial grade, with the stake kits.

• Prepare your edge by digging or rototilling a six-inch deep trough outlining the bed. It's best if the soil inside the bed has been prepped/rototilled before you install the edging, or you might hit it with the rototiller after installation. Cut roots if you have to, because you must get down a clean six inches all the way along the edge.

• Edging goes in with the little curled-up "V" at the bottom facing the bed, not the lawn. Place the edging into the trough, curving it along so that the whole piece is loosely installed. Good edging comes in twenty-foot lengths; cut it to fit using your serrated bread knife, or utility knife.

• If the bed edge is longer than twenty feet, use the connectors that come in the spike kit, but this is a biggie: slide one end of the connector into the top circle halfway, then slide the next piece on, MAKING SURE YOU AREN'T SIMPLY PUSHING MOST OF THE CONNECTOR INTO THE FIRST PIECE. I see this all the time. The connector is about eight inches long, and when finished, you need four inches in one piece and four inches in the adjoining piece. Place the connector in the first piece halfway, lift that end up, then slide the next piece on by pushing down on the connector slightly with this second piece, plus squeezing the circle of the first piece, around the connector. The connector will stay put.

• Now you are going to set the edging into the soil. What most people don't know is that in a finished installation, only the top half or third of the circle should be visible. People set the edging too high, thinking that the whole circle is supposed to sit on top of the ground, so when finished it looks like a hose lying on the ground. No. Only the top half or third of the circle should be visible when finished. Now you'll never hit it with the lawnmower, it isn't visible during the summer, and it still blocks the grass roots from entering the garden bed. Very important.

You'll have plenty of loose dirt on the bed-side of the edging. Pull it down with your hands and push it under the bottom V edge of the edging, so it's loose and forces the edging up an inch or so. Work your way down the bed, pushing the edging into this loose soil so that the top of the circle is as described above.

• Stomp your outward curves. By this I mean you'll notice that where the edging curves away from the bed and out into the lawn, it naturally pulls back from the deep part of the curve. Good edging is a little stiff. So you need to push the edging tight outward, because it will want to flatten the curves you cut into your bed outline. So push it out where it belongs, pull soil down to it, and stomp on it with your feet, to hold it in place.

• Now, before you add any more soil, install the stakes. Starting three inches in from the beginning of the edging, place the pointed tip of the stake into the V at the bottom of the edging. The end you hit with a hammer is bent at a ninety-degree angle. Be sure the short, bent part is facing down (see illustration). (By the way, this illustration was drawn by yours truly, the Renegade Gardener, and is the first illustration to ever appear on the site. Having failed art in kindergarten, I thought it came out rather well. The original illustration, signed by me, fine-point-Sharpie-on-copy-paper, unframed, is for sale for $89.00. Serious E-mails only.)

Here's the most important tip so far: don't pound the stakes straight down into the ground. Don't pound them in at a forty-degree angle, either. Pound them in at a very flat angle, twenty-five degrees max. Pounded straight down into the ground, frost will eventually heave the edging upward. Maybe not all the way, but enough so that it rises noticeably after several years.

Pounded in as close to parallel with the soil surface as possible, however, the edging will never move. You need to push some of the soil away from the stake area to facilitate getting the stake close to perpendicular to the edging, let alone hitting it with the hammer. Use four stakes per twenty-foot length, one at the start, one at seven feet, one at fourteen feet, one at the other end. If you are connecting two pieces of edging, you do need stakes at the end of each joined by the connector, i.e., you'll have two stakes only about six inches apart on either side of a connector. You won't believe what frost can do.

• Pull the soil down from the bed-side so that it's two-thirds of the way up the edging, and stomp all that soil in right along the edging. You're setting the soil hard into the V at the bottom, and that further keeps the edging from heaving out in spring.

• Next filter soil through your hands into the narrow gap left between the edging and the lawn-side. This will never be a perfect fit, there are gaps, so get some soil down on the outside of the edging too, so the grass will grow back tight to the edging.

• Water the edging. Walk along with the hose and water the soil in on both sides. This causes the soil to settle in tight on both sides.

• Pull the rest of the soil from the bed even with the edging, add a little more soil to the grass side, because watering will have made it settle. You're done. Your installation is good for fifty years.

Don't plant evergreen trees without regard to mature size.

White Pine, doomed in 2004.

Spruce, doomed in 2010.

Spruce, doomed, all five of 'em, any minute now.

Properly spaced planting of Black Hills Spruce.

This is a very common blunder I see in every part of the country while out on my travels. Evergreen trees, among the most expensive plants you can purchase, are commonly planted too close to driveways, streets, houses, and fences.

It's so easy to plant them correctly; just look up (or ask) what is the mature width of the tree. Most of the ill-placed trees I see are only off by four to six feet, although on occasion I'll see a spruce planted a good ten feet too close to something that's never going away.

The problem is that a tree planted thus is doomed. It's only a matter of time before the width of the tree results in the homeowner having to hack off the branches. Not only does cutting branches make the tree look less than attractive, it takes away the tree's vigor, and opens the plant up to disease infestation from fungi and insects.

Austrian Pine lend great texture and presence to the landscape, but you need remember that in the right conditions an Austrian will eventually grow 35' wide at the base. Perhaps not the right tree to plant off the corner of the garage. The common white pine? Those babies are going to get 30' to 40' wide, meaning you need to plant a white 15' to 20' from a house, street or driveway. Spruce? The popular Black Hills variety gets 20' wide fairly quickly, and can approach 30' wide at full maturity.

So it pays to do your homework, to learn about evergreens, to add to your gardening knowledge. Most of the time, an evergreen shrub or shrubs is what you really want out towards the front of the yard, let's say in a corner area created by the intersection of driveway and street. Varieties of arborvitae, hemlock, juniper, and dwarf pine and spruce might be more in line with the needs of your landscape. Large evergreen trees look a little better behind a house, off to the sides, or in the front, but only when the front yard is big enough to lend proper scale.

If good height is what you're after but space is a little tight, get to know some of the taller evergreen trees that don't broaden so drastically. A Blue Spire spruce is a relative of the Black Hills strain that stays more columnar, while still hitting 30' in height. A Swiss Stone pine is going to grow upwards to 40' tall, but only expands 15' to 20' wide while doing so. Balsam fir will give you all the height you need, 50' or so, but rarely exceed 20' in width, meaning you can plant one only 10' from a perimeter fence.

Don't DO That will be updated August 1








Don't trim hedges into a "V" shape.

I think homeowners do this under the mistaken impression that the great hedges of the world are vase-shaped. They're not.

Clip hedges so that they are slightly wider at the bottom than at the top. One can occasionally create a hedge with perfectly straight, perpendicular sides if the hedge is running true north to south, but it's risky.

Hedges (evergreen or deciduous) need to be wider at the bottom so that the bottom branches get enough sunlight to stay alive. Clip a hedge into a "V" shape and the bottom branches are shaded by those above, and soon die out. This is also good advice when pruning or shearing any stand-alone shrub.

The great hedges across America and the UK are all wider at the base than at the top, though sometimes subtly so. I so rarely give out homework on the site, but here's one assignment for you: look up the word "batter" in the dictionary. Score big points at your next cocktail party.

Please don't E-mail the Renegade Gardener with a list of 15 questions.

You know me, I hate to be rude, but as the site becomes more popular, the E-mail traffic has become, at times, extremely high. And I like that – keep 'em coming. Sitting at my computer at night, sipping a cup of tea, listening to the Kinks, Bob Dylan, Outkast, White Stripes, etc., answering E-mails, and occasionally chatting back and forth with nice gardeners around the country and the world, is truly the most gratifying part of hosting this site.

But please understand I do not have time to answer multiple-question E-mails, or review attached pictures of your yard, then give out free design work. If you have more than a question or two, contact your local university extension service and find out how to contact a Master Gardener in your area.

Not only will you receive a more comprehensive answer to your questions, it will probably be based in horticultural fact!

Don't use wood chips or shredded bark as mulch in perennial beds.

Trust me, as you gain some years as a gardener, you'll wish you hadn't. Though I can see the reasoning – wood chips or bark fit the bill, they keep weeds from growing in our flower beds, and shade the soil so midday sun doesn't evaporate moisture. And if you put a healthy layer of bark down, it lasts for several years, which is a much easier way to go than using cocoa bean husks or dried grass clippings, which need replacing at least every season.

Ah, but there's the flaw: wanting everything to be easy (see RG Tenet #5). If you want an easy hobby, collect commemorative quarters.

Problem is, perennials expand year to year. They need division, they need replacement, they need to be moved. New gardeners plant their first whiff of perennials and think, there, that's done, I'll never go near that bed again, failing to realize that in two years they'll see their initial effort as laughable, and realize that almost nothing is in the right place.

Now go and try to scratch some granular fertilizer into the soil. Try lifting out plants with your perennial fork. Try to divide them. Try to dig a hole. You have hunks of wood everywhere, mixed in with the dirt, impaled on your fork, and floating two feet in the air amidst the branches of an aster that has tripled in size.

Landscapers are notorious for finishing off a new perennial planting with a layer of shredded bark or wood chips. All they want is for a year to go by without the homeowner seeing weeds growing up in the garden. They don't have to come back in three years when the whole thing needs major surgery. And needless to say, shredded bark or wood chips looks like hell spilling out around a flower bed. What's this wood doing in here?

Remember a simple rule: use a one-season, biodegradable mulch in your flower beds, such as cocoa bean husks, dried grass clippings, shredded leaves, compost, whatever. A minimum two-inch layer, it will last a season then compost down into a nice organic additive to your topsoil. You need to dig a hole or dig up a plant, you pretend it isn't there, it's the same as your soil. The next year, you add more. This is gardening.

Use shredded bark/wood chips only around trees and shrubs; you don't need to dig them up and divide them, you leave them alone. Unless two years later you realize you really blew it.

Don't blow grass clippings or rake leaves out into the street.

Time for my quick, annual tirade against this practice. Seems every lawn service employee as well as half the homeowners in my neighborhood are moving, by one means or another, grass clippings and leaves from their yards into the streets of Deephaven.

We'll get a rain soon, and all that phosphorus-packed organic material will get swept down the streets to the storm sewers, which drain directly into dear old Lake Minnetonka. These materials are the chief cause of eutrophication, a.k.a. excess algae growth in ponds, lakes, rivers, and streams. Lawn fertilizers are only a minor, secondary cause.

Mow your lawn so that as you approach your street or driveway, you're blowing the clippings back into the lawn. Don't rake or blow leaves into the street. And please advise your headphone-encased, Marlboro-smoking, standup mower-surfing, twenty-five year-old lawn care service professionals to do the same.

Don't DO That Archive