One of my favorite spring garden tasks is putting together container combinations. And fortunately, it’s still early in the season and the garden centers are well stocked, so the opportunity is not lost.
Probably the single most recognized planter combo consists of red geraniums, variegated vinca vine, and in the center, a green spike. The arrangement provides summer-long color and good composition — it’s a classic for good reason. This proven formula can be adapted to other plants to create something new. You’ll need a tall, airy center plant to represent the spike, some full, bushy plants around it for substance, and low, trailing plants to spill over the container’s edge. A clever garden writer coined the terms thriller, filler and spiller to identify these key combo elements.
Follow the recipe to create your own attractive, well-composed container combination. Choose three or more types of plants with overall shapes that match these forms. Depending on the size of your container, select one center thriller, ring it with three or more bushy fillers, and surround those with three or more trailing spillers.
Grassy plants are a logical choice for the combo center, but nearly any with an upright, arching form can be used to a beautiful effect.
Red-leaved or variegated spikes offer the classic look with a new twist.
Most greenhouses will also feature an assortment of ornamental grasses in smaller pots, strategically located with the other premium annuals promoted for containers. These present a wide assortment of color and form — and be sure to check the tags for size information so you can pair them with appropriately sized companions.
Purple fountain grass has great leaves and also provides showy, arching flower plumes through the summer. Bronze-leaf sedges offer coppery, slender leaves that look fantastic with peachy-pink and orange flowers.
Millet varieties can be found with bronze, burgundy, or golden leaves. Japanese blood grass is grown for its deep crimson leaves, apple green at the base and deepening to wine at the tips. Blue fescue, blue oat grass and rushes round out the color pallet with shades of blue gray.
Of course, a plant does not have to be grassy to fill that central thriller role in a combination. Any tall, slender annual can fill the bill, including many of the flowering sages (salvia), globe amaranth (gomphrena), cosmos or cockscomb (celosia). Perennials such as the slender, swaying stems of gaura, or upright cardinal flower (lobelia) also work well. Add an exotic touch with tropical plants like taro (colocasia), ornamental redleaf banana, Hawaiian Ti or canna.
An enormous range of plants are suitable for the bushy filler role. Choose plants that are shorter than the centerpiece by a third to a half. Good options for sun include petunia, flowering vinca (catharanthus), marigold and argyranthemum daisies. In shade consider impatiens, coleus and begonia. Many plants with upright flowers like angelonia, salvia or nicotiana will also work here, especially if you’re using a grassy plant for height. For large containers you may use more than one kind of plant in this role, of the same or different heights.
Finish the combo with plants that will cascade over the container’s edge. Sweet potato vine, creeping jenny (lysimachia), ivy, and silver falls dichondra are some true trailing plants that fill the role. You may also choose trailing varieties of petunia, calibrachoa, verbena, alyssum and lobelia to get cascades of flowers.
Once you’re comfortable with the classic combo formula, you’ll be looking for ways to push it for a new effect. And that, of course, is half the fun.