Priority Areas

Selecting one or a few priority areas in your yard can help make the work more manageable. Above all, you want to avoid the mistake of clearing a large area and not being able to replant or mulch it immediately (see Cover the ground).

Start by mentally dividing your yard into sections that have meaning to you. Divisions such as front, back and side yard might make sense. However, you may think about your yard in more nuanced ways, such as “back corner beneath the oak tree.” Don’t hesitate to define and prioritize small areas such as “the 6-foot area beneath my oak tree,” possibly a perfect site to create a “soft landing” as discussed in the last paragraph in Cover the ground.

Sunlight

The traditional gardener’s adage, “right plant, right place,” includes selecting plants that fit with the sunlight exposure in the planting site. Too much sun and shade-loving plants will suffer from insufficient water, heat stress, and possibly death. Too much shade for sun-loving plants can result in poor growth, lack of blooms, susceptibility to disease, and yes, death.

Plant guides and databases express plant light requirements in various ways, frequently and infuriatingly without defining what the classifications mean. Here is a common three-part classification system that the U.S. Fish and Wildlife publication (pg. 8) on native plants for conservation uses:

• Full Sun – direct sunlight for at least six hours a day
• Partial Shade – approximately three to six hours of direct sunlight;
• Shade – less than three hours of direct sunlight or filtered light.

Common variations on the preceding three-part classification include,

• using “partial sun” instead of “partial shade” as the label for the middle category above.
• using a four-part system in which “partial sun” mean 3-6 hours of sunlight, including some hot afternoon sun, in contrast to “partial shade” where the 3-6 hours is mostly gentle morning sun.
• Further subdividing “Shade” into a few hours of direct sun, versus “dense shade” such as in a densely wooded area, versus “dappled shade” where the sunlight never directly reaches the plant but significant filtered light is available.

This terminological cornucopia should not obscure the main message: light conditions form a spectrum from dense shade to day-long direct sun exposure, with a given plant species surviving and thriving in some specific range along that spectrum. It may be a quite wide range, such as for elderberry (Sambucus canadensis) that can live in sun or shade. Alternatively, it may be a quite narrow range, such as for wild ginger (Asarum candanse) that seems to tolerate almost no direct sunlight.

You need know the ranges of light in various parts of your yard in order to select plant species that match those conditions.

You may be able to guesstimate the category matching your priority area by observing it at different times of the day. If you would like more precision, make a sun map and a sun chart as explained in this handout and this video on light conditions, in which the part about sun mapping and charting starts at 5min15sec.

(Note: This is the same video link given in the previous section, Identify priority areas).

Light conditions will vary with the seasons, e.g. changes in the angle of the sun, tree foliage. Consider making sun charts for different seasons, and updating your work when more permanent changes occur, such as downed branches or new construction.

Soil moisture

Like light, soil moisture also represents a spectrum. The U.S. Fish and Wildlife publication cited in the preceding section classifies soil moisture as follows (pg. 8):

• Dry – water does not remain after a rain
• Moist (also called “mesic”) – the soil is damp, and may be occasionally saturated
• Wet – the soil is saturated for much of the growing season

Assessing soil moisture in a given area faces a basic dilemma: you are on top of the soil, trying to assess moisture available to plant roots below ground level. Recent precipitation can further complicate assessment because everywhere may seem dry during a drought or wet after several days of heavy rain.

Yard-owners are likely aware of areas with wet soil because these spots will remain saturated days after a rain. Below are some clues for identifying dry and moist soils.

Dry soil

Moist/mesic soil

Plant guides and databases will indicate a plant species’ requirements for soil moisture.

Unwanted vegetation

The easiest way to remove turfgrass (lawn) and most other unwanted vegetation is through sheeting mulching: cover the turfgrass with cardboard, put mulch or woodchips on top, and leave in place for six months or until the cardboard has disintegrated. A faster method albeit less attractive is to put down only the cardboard and remove it after about six weeks.

Either method avoids the labor of digging up grass and vegetation, plus preserves the soil structure and texture. That, plus all the dead grass feeding the soil microorganisms (along with cardboard and mulch in the first method), creates a healthy underground ecosystem to feed the plants.

Sheet mulching does not work well with very tenacious roots, bulbs, or tubers that store energy for the plant to regrow when light become available. Liriope, English ivy, lesser celandine, and many of the other common invasive plants in Takoma Park are examples.

Removing invasives typically requires pulling them up by the roots, using an herbicide, or both (see common invasive plants for advice on the best methods for removing a given species). Consequently, removing invasives can easily harm new plants. Eradicating invasives before replanting with natives saves frustration and extra labor later.