During my previous career as a Montessori teacher, and my current career as a parent, I have spent many hours observing the way children play when adults do not interfere.  Young children find nooks, places that bring the world to their scale. 

The corner where the fences meet, beneath an arching shrub or a weeping tree, behind tall flowers—these are all candidates for a children’s place. 

Plant the shrubs a few extra feet away from the fence to leave space for play.  Plant helianthus or other tall flowers in a circle, leaving room to play in the middle.  Do not prune the low-hanging limbs of your dogwood or other spreading tree.  Cover the ground with leaf mold that is soft underfoot—and benefits the plants as well.  Check the toxicity of your plant choices.  Many common landscaping plants are poisonous.  

Minor changes in your garden design can make for years of joyful play and a lifetime of happy memories.

Japanese barberry

Japanese barberry.  Why do people plant a shrub with vicious thorns and no pretty flowers to make it worth the pain?  To add insult to injury, Japanese barberry is invasive in 20 states and the District of Columbia. 

Birds eat the berries, which are less nutritious than other sources, and disperse the seeds.  Deer do not eat the thorny branches, so barberry has another advantage over native plants.  Barberry can also reproduce vegetatively.  When a branch tip touches the soil, it takes root.  In this way, large thorny thickets of barberry grow in wild areas. 

Yet, nurseries continue to sell this plant.  It is widely promoted and a glance in any DC suburban neighborhood will demonstrate its success.  A Google search finds far more sites singing its praises than warning about its invasiveness.  Hopefully Invasive Species Awareness Week will reach garden writers and garden center employees as well as the general public. 

Photo: James H. Miller, USDA  Forest Service, Bugwood.org

Purple loosestrife

Aliens in old science fiction movies arrive in space ships, look frightening and threaten to take over the world.  Well, aliens are real.  But they look beautiful and you drive them home from the garden center in your own car.  They do take over the world, however. 

National Invasive Species Awareness Week is February 26 – March 3, 2012.  As per Executive Order 13112 an invasive species is defined as “a species that is non-native (alien) to the ecosystem under consideration and whose introduction causes or is likely to cause economic or environmental harm or harm to human health. ”

How do I know whether my garden plants are harming the environment?  Do your homework.  Maryland Invasive Species Council has a list of invasive plants at http://www.mdinvasivesp.org/list_terrestrial_plants.html .  Virginia’s Department of Conservation and Recreation has a list of invasive plants at http://www.dcr.virginia.gov/natural_heritage/documents/invlist.pdf . 

Then go out in your garden, identify the invasives, and make plans to put native plants in their place.  Even if the aliens are as pretty as the purple loosestrife in the photo.

Photo: Eric Coombs, Oregon Department of Agriculture, Bugwood.org

A rain garden has been excavated deeper than is typical for a flower bed.  Some of that excavated soil is moved elsewhere on the property. The remaining topsoil  is mixed with compost and sand to make a more permeable medium.  When the mixture is replaced in the hole, it should be a few inches lower than the surrounding landscape.  

Choose native plants that will appreciate the moist environment of the rain garden.  As always, consider the amount of sun the area receives and the mature size of the plants.  Trees and shrubs, as well as perennial flowers, grasses, and ferns may be used, depending upon the size of the rain garden.

A rain garden must be located in a place where rain can flow in and stay for up to 48 hours.  By that time, the water will have percolated into the soil to recharge the water table.  Mosquitos will not have time to breed.  Locate the rain garden at least 10 feet from your house.  Notice the way the water naturally flows in your landscape to help you locate your rain garden in a place that will work. 

Your rain garden can help balance the effects of the impermeable surfaces of roofs, driveways, patios, sidewalks, and roads. 

They are inexpensive.  They are fast-growing.   They are readily available at the big-box stores as well as specialty nurseries.  So you buy a few to make a hedge and in a few short years you have created a nightmare. 

Fifteen feet wide for an evergreen is different than fifteen feet wide for a deciduous tree.  A deciduous tree will allow you to walk beneath it.  An evergreen, such as a Leyland Cypress will not share the space with you.   Are you willing to give up 177 square feet of your backyard for a single Leyland Cypress?  If you plan a hedge, multiply by the number of trees you are planting.

They are very tall.  Do you really need to screen an ugly view that is six stories tall?  Well, you say, I’ll keep it pruned.  If you do it yourself, that involves a very tall ladder and sticking to a schedule or this fast-growing tree will quickly get out of hand.  If you pay a professional tree company, the expenses will quickly mount. 

They are dense.  No light comes through.  The rooms of your house shaded by the Leyland Cypress will be permanently gloomy and dark.  The part of your garden shaded by the Leyland Cypress will be permanently gloomy and dark.  Not much will grow in competition with the shallow roots and deep shade.  Is it worth it?

They are unfriendly.  When you plant a Leyland Cypress, you are dooming your neighbor to the same pruning work and looming darkness—and they didn’t even have a say in the matter.   

So, gently set down that deceptively cute Christmas-tree-like Leyland Cypress you were about to put in your cart.  Go home, measure your space, do your research, then go buy a different tree that you will make you happy for decades. 

So many sunny, mild days, but it’s not spring yet.  We can dream and plan, though, starting with spring-blooming Virginia bluebells. 

Lucky hikers who find patches of Virginia bluebells treasure them.  If you can recreate their preferred conditions of moist soil and shade, you can bring some of that magic to your own garden.  Never collect plants from the wild.  Cultivated plants can be purchased from quality local nurseries. 

Virginia bluebells’ ephemeral nature is part of their charm.  Enjoy them while you can.  In the summer, the plants go dormant.  Try a companion planting of native ferns to soften the bare places dormant bluebells leave behind.

None of the gardening websites, including those of university extensions, gives that advice.  All of them go on for pages and pages of solutions, making shade grass seem like the most natural thing in the world.  It is not.  Grass needs sun to grow well, period.

When I take a walk in the woods, I do not see grass growing beneath the trees.  I see an herbaceous layer of ferns and woodland flowers—at least in the places not completely consumed by the invasive English ivy. 

Lawn care damages trees.  String trimmers and lawn mowers damage the roots and trunks of trees, shortening their life.  Tree roots are in the top two feet of soil and the feeder roots are in the top six inches of soil, so the lawn is competing with the tree. 

Just pull those last little tufts of grass out from beneath your trees—you know they’re pathetic anyway—and put two or three inches of mulch out to the drip line instead.  Your trees will be healthier, your yard will look nicer, and you will save some time on lawn care.

“No, I don’t want any more shrubs in my yard.  They’re too much work,” says a man who has asked me to design his garden. 

Puzzled, I think about the structure shrubs provide.  Their flowers, leaf color, leaf shape.  Low maintenance.  Water deeply for the first season, then let Mother Nature take over.  Decades of beauty for a small initial investment of time.

“I’ll have to trim it every weekend,” he complains. 

I get it now.  He’s thinking about meatball landscaping.  Plant a fast-growing exotic shrub, like euonymus, or an exotic shrub with an overwhelming mature size, like yew, then beat it into submission with your hedge clippers.  Voilá.  A yard full of green spheres. 

There is another way, I explain.  Choose a shrub with a mature size that fits its space.  No 20-foot tall shrubs in front of the living room window.  No eight-foot-wide shrubs planted right next to the front walkway. 

Choose a shrub with a natural form that you find pleasing.  Every shrub does not need to be a tight green ball.  Some shrubs are tall and slim.  Some shrubs are wide and cloud-like.  Some shrubs have nice “bone structure,”  branching habit.  Allow the shrub to grow the way its genes tell it to grow and you will not always have to manipulate it to be something it is not. 

Don’t choose based on the juvenile form you see at the nursery.  First, go to a botanical garden near you and look at mature specimens.  Often they are labeled.  If they are not, take a photograph and ask a Master Gardener to help you identify the shrub.  Then, do your homework and find out the mature size and growth rate.  A little initial planning will save you a lot of work in the long run.  And it will look good.

Your garden is part of nature, not a sterile laboratory separate from it.  Remember the food web that you learned about in fourth-grade science class?  Plants make food from the sun; insects eat the plants; small animals eat the insects; larger animals eat the small animals, etc.  Remove insects from the equation and you remove the other animals as well.

Our beloved birds.  We fill feeders with seed and suet, fruitlessly trying to foil squirrel raiders.  We build elaborate bird baths and bird houses, locking the cats indoors. Yet, we are starving the birds.  Most nestlings feed on insects, even those who will eat seeds or fruit when they become adults.   No bugs, no baby birds. 

So, relax.  A few nibbles won’t spoil your garden.  In fact, it will bring your garden to life.