May is one of the busiest months in the garden. Until now, we could put off a garden chore for a week or two. Today, everything that needs to be done needs to be done now. All of a sudden, the once-dormant lawn needs regular mowing. Weeds that were nonexistent two weeks ago are ready to set seed. The rhododendron is in full bloom one day and needs to have its sticky, spent flower heads removed the next. At this time of year, one garden chore leads to another.
The early spring bulbs have come to the end of their seasonal show. Let this be a reminder to plant summer-blooming bulbs, corms and tubers. Bring tender dahlias and begonias out of storage if you packed them away for winter. Caladiums, cannas and calla lilies can also be planted out in the garden now. Most are perfect for pots or hanging baskets.
Gladiolas are also ready to go out in the garden. People who love “glads” can’t get enough of them. They come in an expansive array of colors and add an elegant dimension to flower arrangements. Some gardeners complain to me about their short flowering period. To extend bloom time, plant a portion of your gladiola bulbs every other week for a month. Newer plants will flower about the time the first plantings fade.
The second complaint about glads is how easily they topple over in a summer breeze or after an overnight rainfall. It is true, they have a tendency to fall, especially if the bulb is planted close to the soil surface and the plant grows lean and tall. Trying to stake a group of glads together just emphasizes the look of the “femme fatale.” The whole group swoons together as if staging a Greek tragedy. It’s best to stake gladiolas individually. A tall, thin wire stake with a small loop at the top that fits around the stem works best.
As a guide to planting depth, most bulbs should be covered with twice their own depth of soil. If the bulb is an inch thick, cover it with 2” of soil. If your tubers are dry and shriveled after their long storage period. you can plump them up by soaking them in water for a day before you plant them. Divide large clusters of dahlias before they go into the ground to increase your number of plants or to share with fellow gardeners.
While you are out working in the garden beds, put wire plant grids and other supports in place so that perennials over two or three feet tall can grow up through them. One of the easiest stakes to use is the flexible “Y” stake. The support portion of the stake is a very sturdy, hollow metal tube with a pointed end that pushes easily into the soil. At the top, two flexible arms wrap around a plant as loosely or as firmly as you choose. They look best if you use the arms to hold up the interior body of the plant, allowing a few of the outside stems and flowers to stand freely outside the confines of the stake.
If you have established rhododendrons, azaleas, or camellias in the garden, fertilize them after their spring bloom. Use an acid-based fertilizer designed specifically for flowering broadleaved evergreens. As early-blooming trees and shrubs finish flowering, prune to shape. If the ground has warmed up, you can also add a layer of mulch to help maintain soil warmth and hold water in the soil.
Daylilies that have been in the ground for several years may need to be divided. These plants divide easily and each division will flower this year if you get the job done early in the season. Dig the old plants completely out of the ground. Rinse off the dirt so you can see the crown and root ball. Using a sharp knife or shovel, make a clean, straight slice through the crown. Get each division into the ground as quickly as possible and water well.
Fertilize bulbs as the flowers fade and begin to deadhead early-blooming perennials. Pinch back fall-flowering plants such as chrysanthemums, garden phlox and asters so they grow more compact and bushier before blooming. It’s a good thing the days last longer in May or we would never have time to get to every spring chore. In May, a gardener’s work is never done, which is fine by me. One more reason to be out in the garden.
Robb Rosser is a WSU-certified master gardener. Reach him at Write2Robb@aol.com.