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Allan designs and plants flowering gardens in Montreal, Zone 5 [USDA Zone 4] .

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Entries in herbicides (4)


Six Steps to Creating Grassless Tree Lawns and Shade Gardens

A reader submitted the following inquiry:-

I am dying to transform my Williamsville NY tree lawn into something more than grass! I am thinking wildflowers but also need to keep in mind that I can’t have anything in the lawn that would obstruct vision when entering exiting the drive. I'd like to start this soon - any helpful ideas, suggestions!!!

Here is my reply:-

Step One. Decide upon a desired appearance of the completed tree lawn when grass has been removed and plants have been installed. If this proves to be a challenge, close your eyes and dig deep inside yourself to imagine the finished project. It’s easier than you might think. That idealized image will influence the choices you make as the project progresses.

Keep in mind that there is a difference between a tree lawn and woodland. The tree lawn may be a studied, deliberate composition while the woodland has a more spontaneous, naturally surprising feel about it.

The most inspiring advice for planting a beautiful spreading, woodland is found at the garden blog Carolyn’s Shade Gardens. This site is a beautifully illustrated treasure of suitable information.

In addition to the overall visual impression or mood that one wants the garden to convey, consider a garden’s personality. The choices are "wild and messy", "neat and trim" and "casual”.

Wild and messy refers to a combination of wildflowers, self-seeding woodland perennials, and other plants whose forms tend to be untidy.

Neat and trim implies a composition of tame and mound-like plants that respect a predetermined linear planting design. Such disciplined plants increase in size at a conservative rate.

A casual garden uses the same mound-like tame plants that are found in neat and trim but in an unstructured, informal collage-type arrangement. This style of planting may be achieved with a deliberately abstract placement of plants or by distributing them randomly and haphazardly throughout the garden.

Step Two. Select a procedure for effectively removing grass. That process will be influenced by one’s acceptance or disapproval of herbicides, [a very controversial topic, with valid arguments pro and con] and by local environmental by-laws that govern the use of such products.

When evaluating a grass removal procedure, one must consider the amount of time available for the task, the amount of physical energy one can muster, and one’s comfort with mechanical, chemical, and organic methods. In her book Beautiful No Mow Lawns, Evelyn J. Hadden identifies 5 different ways to remove grass from an existing lawn. It’s a must read.

Step Three. Inspect the density of the soil. Have the trees reached a maturity that makes the soil so dense with roots that it is difficult to dig there?

If the soil is root-bound, there are two options: One may use a roto-tiller to chop up the tree roots that grow close to the surface. While this method is effective, it can risk compromising the health of the trees. Some mature trees might be unaffected by surface roto-tilling, while others may be damaged. [It is wise to consult an arborist for advice on this subject]. Or, one can build raised beds about two feet high, above the root-bound soil, to create a happy growing place with minimal damage to the trees.

Soil amendments that are needed - and those that are always beneficial, like compost - should be considered at this point.

Step Four. Research the garden’s USDA hardiness Zone; that detail is important when selecting plants.

Step Five. Determine if the tree lawn creates part shade or full shade and if its soil is dry, moist, or normal. Dry means that neither natural rainfall nor irrigation hits the lawn. Moist implies a garden that is damp more than it is dry.

The information gathered will help determine what is or isn’t plantable around the trees. When researching suitable plants, or when perusing an online garden catalogue, look for adjectives in the product descriptions that match the garden’s growing conditions.

[It is at this point that one also starts paying attention to the mature height of suitable plants. My reader specifically requested plants that do not block her line of vision when entering or exiting the driveway.]

Step Six. Evaluate the role of aggressively spreading plants and ground cover perennials that sometimes grow for "miles". Is the area encompassing the tree lawn ample enough to accommodate such plants?

A garden is not a naturally occuring place. It is created by humans from a figment of imagination and, as such, it remains forever a work in progress. These six steps are only the beginning. There will always be something new to consider, to add, or to remove.


Beware of Gardening Tabloid Headlines!

I have just read a controversial article posted to the online news source Huffington Post, an organization that is often prone to creating emotion-stirring, undeserving headlines out of un-newsworthy occurrences. The title of the article  reads:- Roundup: Birth Defects Caused by World's Top Selling Weedkiller, Scientists Say".

Disconcertingly, upon closer examination of the entire article, a reader can confirm the inciting nature of the headline. It is worrisome that too many will digest it as an indisputable fact about Roundup when that product still remains under scientific scrutiny.

To the extent that the Huffington Post headline reflects the opinion of one group of scientists, the news article is accurate. However, since that opinion has not yet been corroborated by other scientists who follow more stringent research protocol, that article is not truthful. In fact, it will only stir up the emotions of dedicated and respected environmentalists that have already come to the as-yet scientifically uncorroborated conclusion that glysophates, even if properly administered, are toxic to living things.

By reading the entire article, one learns that the scientists’ statement reflects the finding of a flawed study. Respected organizations that monitor the possible toxic effects on humans of suspected substances report that an unflawed and proper investigation of such an allegation is problematic because testing for toxicity on humans is risky. Nevertheless, their opinion on this matter still requires further research - research based on accepted, rigorous scientific protocol. Surprisingly, that organization will not issue a definitive statement on the subject for another four years!!!

As responsible gardeners, we are constantly on the lookout for safe ways to clear aggressive, unwelcome vegetation from our gardens and farms. Unfortunately, many of the healthier alternatives are not efficient. Time and speed are important attributes of any herbicidal action because both gardeners and farmers, especially those living in colder climate, are in a perpetual race with nature to clear, plant, and harvest within a restricted time frame.

Those of us who grow decorative plants or food understand that anything that can kill vegetation probably will kill other living matter as well, and that includes humans. Up until now, that has been our unscientific gut feeling. We also recognize that it is doubtful there can ever be such a thing as an efficient and safe - for - living - things herbicide. However, since we are unable to stop gardening for pleasure and we must grow nourishment in the most efficient manner possible, rightly or wrongly, we are destined, for the time being, to tempt fate by continuing to use herbicides.

Imagine the upheaval that will occur in the gardening and agricultural industries if the scientific protocol-respecting research reveals that glysophates are indeed harmful to all living things, no matter how carefully they are used. What will we do then? It is also very worrisome that scientific bodies are only beginning to publicly tackle the subject of glysophate's toxicity now that Monsanto's patent for this product has recently expired. What does that tell us about a respected, international community of scientists who are forced to depend upon big business to sponsor their research?

Read the entire Huffington Post article here.


Update on a Safe Weed Killer

To obtain this product, click on the image to link to the store of Pharm Solutions. On February 10, 2010, I posted a blog about Weed Pharm, a safe, organic weed killer made by Pharm Solutions with industrial food grade acetic acid. The intention was to test it and report back to my readers. Although I had purchased the product online early in the season, a cold spring season delayed my ability to experiment with it. Only in the last four weeks have I been able to use it. Boy is it effective!

For example, at 8 AM yesterday morning, a very hot and sunny day, I sprayed Weed Pharm on a strip of earth measuring 20 feet long and 2 feet wide that was smothered in weeds. By noon of the same day 99% of all of the weeds in the strip were toast, literally, because they shriveled up and turned brown. Repeat: shriveled up and turned brown in 4 hours. A few perennial weeds remain because they require more than one application of Weed Pharm. That is a small task that I am happy to undertake, given how efficient and quickly this product works.

Compare this timeline of four hours to the prolonged time for systemic weed killers to take effect. These glysophates usually take over a week or more to produce results and the extent of harm that they might cause to our planet and to us is not yet completely revealed or fully understood. However, the industrial food grade acetic acid used in Weed Pharm is also used in the manufacture of pickled foods and salad dressings and its organic classification is certified by the USDA. The only cautionary note is that eyes and skin need to be protected because the concentration of acetic acid in this product is 20% compared to 5 or 7% in ordinary kitchen vinegar. I wear prescription glasses so that my eyes are protected and I use leather gloves for all gardening chores so that my hands are sheilded from harsh substances.

I am pleased to have found Weed Pharm; an effective weed killer that replaces toxic herbicides without polluting the environment or placing users health at risk.


Smothering Aegopodium, an Unwelcome Perennial

A ritual takes place in many shaded gardens around the world. It begins with homeowners frustrated that nothing beautiful will grow in their sunless gardens. Inquiries and suggestions ultimately lead them to plant Aegopodium. This groundcover, aka Goutweed, grows in the shade and thrives wherever most other plants cannot survive. To the unsuspecting homeowner, it is an attractive perennial with eye-catching leaves. One variety has foliage, beautifully variegated in green and white, which illuminates shady spots. However, to the seasoned gardener, the plant is a monster.

Several years will pass and the Aegopodium will have spread far beyond its intended location. Homeowners will attempt to lift it out without success. They will bury it with more soil, but it will manage to percolate upwards. After a few years of trying to get rid of it, frustrated homeowners will look for advice, once again.

Removing Aegopodium requires strategy because it cannot be eliminated by lifting. Its roots are too stubborn and too pervasive to respond to manual or mechanical solutions. Glysophate, a systemic herbicide sold under several brand names such as Round Up or Wipe Out, is needed to kill this plant. Alternatively, it may be smothered by covering the plant with an industrial strength semi-permeable membrane called geotextile.This sheeting is then camouflaged with anywhere from one to two feet of earth, or mulch. Earth is more effective because it is heavy enough to keep the membrane in place. The operative word here is industrial strength; consumer grade membrane is not strong enough to fight Agepodium. 

To replace the about-to-be smothered groundcover, select appropriate shade loving plants and insert their root balls beneath the geotextile. Simply slash at the geotex with a very sharp blade to expose the earth below, dig a hole for the plant, insert plant, back-fill with earth, replace the geotex and camouflage with earth. The semi permeable textile will allow water to seep through to nourish the roots growing beneath but will not permit plants, targeted for smothering, to grow up through it. If the homeowner needs a replacement ground cover, consider planting Epimedium, which is availble in both green and variegated cultivars. While it does spread, the growth is controllable. Experiment by planting it in the earth above the geotex.

The landscapers that work in my neighborhood have been attacking Aegopodium for over thirty years. They have decided that smothering with a strong membrane is the only safe solution. In years past, they might have considered using herbicide. Today that is no longer an option. Some of them have lost a colleague to fatal diseases that have been linked to exposure to toxic substances. Now, they refuse to touch even those products, like Glysophate, that are advertised as safe. Local governments, that have already banished other toxic herbicides, are slowly introducing legislation to banish this one, as well. I suppose that landscapers already know what we are about to learn.