Q: I want to add spring bulbs to my garden but have limited space given how many mature perennials and shrubs are already growing there. Can I squeeze them in somewhere else?
A: Autumn is bulb-planting season for spring-flowering jewels like tulip, daffodil, crocus, aconite, hyacinth and snowdrops. Fortunately, they don’t take up nearly as much space as your typical perennial in terms of planting site. I would not dig into the root system of an established perennial or shrub — too risky for causing damage that might result in dieback or reduced overwintering success — but you can certainly fit them into spaces between. You don’t want too many under the canopy of a shrub. Depending on how early it leafs-out, the shrub could block needed sun and rainwater, but around its perimeter should be fine.
Good companions for early-flowering bulbs are late-sprouting perennials, so that by the time the bulbs are looking ragged and losing foliage for summer dormancy, the perennial is hiding it with fresh foliage.
One creative option is to scatter some of the minor bulbs in your lawn, if you won’t be walking on that area too often and compacting soil or crushing foliage, and if you don’t need to start mowing soon after blooms begin. Candidates include crocus, glory-of-the-snow (chionodoxa), Siberian squill (scilla siberica), winter aconite (eranthis), reticulated iris(), and snowdrops (). Be advised, though, that a few of these species might be prone to naturalizing outside of your lawn, so use caution around woodlands and parks.
Native alternatives with bulb-like underground structures include spring beauty (claytonia), squirrel-corn (dicentra canadensis), and Dutchman’s-breeches (dicentra cucullaria), though claytonia is the only one that may stay short enough to be mown-over and whose foliage blends in well with the grass. Many of our native ephemeral wildflowers — early-season bloomers that go fully dormant come summer — are unfortunately harder to find for purchase.
Growing bulbs in containers would be your other option, but this can impact winter hardiness since the bulb’s root system is fully above-ground, not benefiting from the insulation of being planted in the earth. Potting mix also dries-out faster than in-ground soil, so it might be challenging to make sure dormant bulbs in pots don’t get too dry while also not accidentally overwatering them. If the container is large enough, you can layer two or three tiers of bulbs at different depths so they bloom in succession, or use bulbs planted below annuals or shallow-rooted perennials to provide summer color. Bulbs are planted at different depths depending on the species, though, so take note of planting instructions when you select which to purchase and decide where to plant.
Q: My veggie beds are done for the season. Should I leave the leaves until spring for wildlife?
A: Not in this case, no, because crop debris can easily harbor pests and pathogens that will overwinter and begin new infestations/infections next season if not removed. Minor diseases like powdery mildew or nuisance pests like aphids are less of a concern, but more substantial diseases like downy mildew and pests like allium leaf miner are best managed with prevention.
You can compost contaminated debris at home only if your pile reaches the adequate “hot composting” temperatures for the right duration — typically a few days at a minimum. Otherwise, the pests or pathogens will survive composting and render the finished compost risky to reuse in beds. As a sustainability compromise to throwing it away, you can probably send the debris to your local landfill as yard waste, since many facilities will hot compost this material to make it suitable for residents to pick up later as finished compost.
Debris that isn’t contaminated with anything of concern can be used as a mulch, like leaf litter, or you can set it aside to compost elsewhere and sow a cover crop on the bed now. If you are new to using cover crops, choose a small-scale demo to try (perhaps one veggie bed out of several) to see how it works for you. Our Cover Crops for Gardens page lists several species and when to sow them. Experimentation will be easiest if you select a cover crop for a bed you don’t intend to plant too early in the season.
University of Maryland Extension’s Home and Garden Information Center offers free gardening and pest information at extension.umd.edu/hgic. Click “Ask Extension” to send questions and photos.