“Your garden looks like an estate!” That comment really surprised me, but I realized that there is one thing this little yard has that most yards do not: beds with clearly defined edges and swaths of plants that are the same variety. Edges and swaths lead the eye around, and can make your yard seem both larger and calmer.
Fall is a great time to think about what changes you would like to make to your yard; many plants can be divided and moved around now that the temperatures are cooler. Summer’s damage can be appraised, and gardening mistakes can go discreetly into the compost pile.
Today we are on the edge and in the shade, specifically with perennials that are visible for the entire growing season. Crested irises, hostas, and wild ginger are good for edging in the shade. These plants also work in masses.
Observing Your Yard
You need to know where the sun and shade are at various points of the growing season, as well as which areas are wetter or drier than the rest. If you have just moved to a new home, I recommend observing the yard for a full year before you start making any major changes beyond removing serious problems like Japanese honeysuckle, English ivy, or poison ivy.
A piece of plain paper will be just fine. Pull your address up on any mapping program—Google Maps, MapQuest, or Maps, for example—and draw a map of your property in a drawing program or on a piece of paper—you can always get the drawing into your computer by taking a picture of it and sending it to yourself. You don’t have to get too fancy.
Obviously you are not going to be calculating how many plants to buy or swap for with a plan like this, but it will help you figure out what you can consider planting.
Creating or Updating Edges
How do you decide which massing plants could be useful for edging? Consider their growth habits. Geraniums, which I do love, are great for massing, but a little too unpredictable for edging in my mind. They fling their seeds around; you would be chasing unwanted seedlings, which is not a hard job, but more likely than not, it is an unwanted one. Iris cristata, on the other hand, sends out short runners and grows rhizomes right on the surface. See Ominously Springlike, the Other Shoe Has Finally Dropped.
Partial Shade and Moderate Water: Iris cristata
In Michigan, Iris cristata is gorgeous for about a week in May. The irises in the picture below get sun in the morning and early afternoon only, and that flower bed does not dry out too much.
The balance of the year, Iris cristata is a tidy bedding plant that will stay nice as long as it doesn’t get too droughty. It needs partial shade; it blanches in the sun and does not bloom well in full shade. The further south you are, the more shade it will take, apparently. In the southeast, it is considered a shade plant.
Light Full Shade and Occasional Dryness: Hosta plantaginea
If your shade is somewhat drier, you may want to consider hostas. They can make a terrific border, if you choose a variety that’s the right size for your space. The hosta below is the plantain lily, a husky midsize hosta. It requires a fair amount of shade and tolerates our dry spells. It may protest a dry spell mildly with somewhat fewer blooms. If it gets too much sun, the leaves will bleach and burn.
Dry Shade: Carex pensylvanica
Pennsylvania sedge, Carex pensylvanica, is an excellent plant for dry shade. It is a ground cover in the wild, so it is a natural for any massing job in the shade.
Carex pensylvanica spreads by rhizomes, so it is unlikely to pop up unexpectedly far from the edge you are making. It stay green when the lawn goes all tan in August.
Mesic Shade: Asarum canadense
Wild ginger requires more mesic conditions—technobabble for “moderately moist; would not dry out much.” I have it in a border that required water twice this past August, surrounding my kitchen garden.
The swath below is off-camera, to the left of the middle bed in the photograph above. So what happened there? At least two weeks of relentlessly sunny days, with a rather slender magnolia providing little shade to the south end of the ginger—the really sad-looking plants.
In retrospect, I should have watered it, but I am not sure it would have helped. It simply got too much sun. A month and a few rains later, it is still clear which area had dried out too much in August. According to the Ladybird Johnson Wildflower Center, it will not “grow in the high summer heat of Zone 8.” We are in Zone 6.
Looking at these two pictures, I am leaning towards creating a yin-yang symbol by replacing the damaged ginger with something else edible and with a different texture. Thyme? It may be be too shady for thyme.
Defining the Edge of the Edge
The non-plant part of edging is separating the bed from the surrounding lawn. Be sure that you create that all-important shadow line: the drip edge of the plants should be just inside the edge of the adjoining lawn.
In the case of the wild ginger under the magnolia, there are bricks laid in a herringbone pattern that the wild ginger foliage hangs over. This prevents the edge of the lawn from being shaded out.
Generally, I just cut an edge with a spade and maintain it with a scuffle hoe—the kind with the wiggly stirrup.
Conclusion
These plants can all be moved in the fall. Divide existing plants to transplant as explained in Dividing and Transplanting: An Example Project and Beginner’s Guide.
If you buy or swap plants, check the condition of the roots. It there are wood chunks and woody, wiry roots; a solid brick of roots; slime; or dead roots in the pot do not let that plant follow you home!