Building those boulevard gardens
Weeds. Mowing. I don't mind mowing until I get to the curbside. The sand and salt the plow throws on the area during the winter often leave us with a problem area that is more grit than soil, more weeds than grass. How to improve the area has led me to look at the boulevard or street-side garden concept. I've begun to dig deeper into the idea of making this change in my front yard.
I wondered about what plants would work best, if the city had any special regulations and how to best cope with the sand and salt. Check with your city to see if it has plant height regulations for boulevard plantings. To avoid accidents, it's important to know where the various underground utilities such as water, gas and electricity run before digging, especially if shrubs are part of the plan.
The boulevard is a harsh home for plants. It's hot and dry, plus deicers and snow piles can stress plants. Regular soil tests will help identify any soil problems that need to be corrected. Pick your favorite method for preparing the area for planting. A no-dig plan using newspaper and wood chip mulch is one option. Amending the soil with compost and peat is another.
Keep in mind that the plants closest to the curb will probably suffer the most from sand and salt or other deicers. A one- to two-foot strip of mulch by itself or planted with annuals, or a mower's width of grass to provide some distance from the street for the perennials. I think I'll opt for the mulch.
The biggest challenge for me was finding herbaceous perennials with a fairly high tolerance for salt and hot, dry conditions. I was pleased to learn that some good variety was possible. Baby's breath, dianthus, euphorbia, tawny daylily, Stella d'Oro daylily, lupine, sundrops or evening primrose, penstemon, creeping phlox, phlox, various sedums, lamb's ear, gaillardia (blanket flower), candytuft, catmint, coral bells, native asters, black-eyed Susan, hostas, artemisia, yarrow and armeria (sea pink or thrift) allow for an interesting mix of plants.
To the perennials add some attractive ornamental grasses. Karl Foerster Reed grass (Calamagrostis xacutiflora), blue oat grass (Helictotrichon sempervirens) and switch grass (Panicum virgatum) and Elijah Blue Fescue are among ornamental grasses with salt tolerance.
Including some bulbs for early spring bloom and some annuals such as petunias will extend the season for your boulevard garden, just as for any other border. Since most perennial borders take up to three years before looking the way we expect them to, annuals will fill in what appear to be empty spots until the perennials grow to a mature size.
When planning the boulevard garden, do consider the problem of soil erosion caused by poorly designed or high-crowned gardens. Avoid mounding soil. To prevent soil from washing into the street and affecting water quality, keep the final mulched surface of the garden an inch or so below the curb or sidewalk. An option is to add front edging of block so the bed will be even. Shredded hardwood mulch or the mulch of your choice will help control weeds, retain soil moisture and prevent erosion. I think I'd better start planning.
Refer to the revamped and updated University Of Minnesota Extension Service web site
www.extension.umn.edu/garden/yard-garden/ for more information on horticultural topics.