January / 2004
At Home in the Garden

Common garden pitfalls
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Too much of a good thing always turns out badóeven in your garden. Two common garden pitfalls is putting in too many plants and using too much mulch.

No matter what your garden style is, itís always important to space plants out appropriately when installing a new landscape, giving them ample room to grow. Too many plants in too little space may look good right after planting and for the next year, but they will start to grow. By the third year you begin to realize you could have saved some money if you had bought and planted fewer plants. During the fourth or fifth year, you realize you may have planted yourself a maintenance nightmare.

Plan for plants
Make sure you have your plan on paper and a planting plan with the approximate number of plants needed according to the size of the space. Make sure you know how large the plants actually get for your area and plot their size to the area.

The error sometimes starts when you buy small, economical plants in 1-gallon containers. This small plant may only be 1 foot wide now, so itís hard to imagine that it will grow to be 5 feet wide. Then there is the question of how long you will have to wait for it to get big. If you donít have the time or the patience to wait, I always suggest purchasing larger plants as opposed to over-planting the space.

This simple, more environmentally friendly approach in most cases turns out to be the more economical choice. For example, if the plan calls for three boxwoods and you buy the larger 3-gallon size at $25 each, your plant total is $75, compared to over-planting the area using six 1-gallon sized plants at $14 each, with an $84 total. You just saved $9 and correctly spaced your boxwoods to grow and mature naturally with little or no maintenance or pruning necessary.

Choosing mulch
Another common garden pitfall: the incorrect use of mulch in the garden.

There are many types of mulch to choose from, so how do you know which one to pick? When purchasing high-quality bark or composted mulch from a reputable source, it is simply a matter of personal preference. Pick the one you like the most that complements your style and planting the best.

The most common types of mulch available listed from highest to lowest price are: grade A all-bark cypress; pine needles (sold by the bale); pine bark chips (available in a wide variety of chip sizes); dyed, shredded hardwood such as black magic or black satin; Grade B cypress (no bark, mostly chopped or shredded wood pieces); and natural shredded hardwood (includes bark and wood).

How do you know high-quality mulch from another? They should be correctly composted, giving them an earthy smell, not fermented and not slippery when wet, which is a sign that composting is not complete. They should be consistent from bag to bag. If itís an all-bark mulch it should be all bark; if itís a shredded hardwood the pieces should be adequately and evenly shredded. When composting for mulching purposes at home, chopped or shredded woody products should be combined with materials high in nitrogen or nitrogen itself, and within two to four months a usable product is ready for the garden.

How to apply mulch
Research shows that high-quality mulch applied to a depth of 2 to 3 inches in landscape areas is adequate to provide maximum weed suppression, which is the most important job of mulch. Mulch applied to a depth of 4 to 6 inches or deeper is not only a big waste of money, but when applied at this depth actually increases root rot and trunk-decay diseases. Mulch should never be applied in excessive amounts or piled up around the trunk of any plant. Mulch applied in the correct amount promotes plant health and vigor, and is most important to the plant in the first few years after planting.

Also avoid products with a high wood content, or that sour or fermented smell. If you find yourself with products like this, pile it up and continue the decomposition process for a few more months before applying it to your landscape.

Always soak or water your mulch in after application. This helps in the prevention of unwanted fungi developing on your mulched beds. If you have seen artillery or shotgun fungus form on your mulch and stain your house, you will understand why this is important.

When in doubt of the quality of the mulch you are using, always apply it in the fall or winter when disease pathogens and our plants are the least active. This provides time for additional decomposition or leaching of salts, which would suppress the establishment of beneficial microbes in new growth necessary for nutrient uptake and health and vigor of our new or established plants.

Find a good source for mulch, choose the same type of mulch each time, and apply it to all your new plantings when installed and to established plantings when needed. The mulch should not steal the show: that is what the plants are for!