Gardening With Allen: Know right time to plant bulbs
By Allen Wilson for The Columbian
Published: April 16, 2022, 6:00am
Share:
I have noticed tuberous begonia, lily, dahlia and gladiolus bulbs for sale in local stores. Can they all be planted outside now?
Flower bulbs fit into two basic categories: tender bulbs that can be damaged by frost and should not be planted outside until late May, and hardy bulbs that can be planted while the soil is still cool and frost can be expected.
Tuberous begonia bulbs (tubers) are tender and should be planted inside as soon as possible. The concave portion of the bulb should be placed up. This is the side where the shoots are located. The roots come out of the convex (rounded) bottom of the bulb. Begonias should be planted with an inch or less of soil covering the tuber. Begonias can be transplanted outside when shoots are only a few inches long in late May or early June.
Dahlia bulbs are also tender. The best procedure with dahlias is to plant one bulb (tuber) per 6-inch or 1-gallon pot. Plant so that the eye or growing points are an inch below the surface with the slender tubers pointing down deeper into the soil.
Lily and gladiolus bulbs are hardy and can be planted outside by mid-April. Lilies are so hardy that they can be left in the ground through the winter. They can be planted in spring or fall. If planted now, they will develop a good root system and emerge from the ground in about three to four weeks. Gladiolus bulbs can be planted from mid-April until June in order to spread out their flowering times. If you plan to use your glads as cut flowers, make at least three plantings at three week intervals to give you cut flowers over a longer time period.
Other summer flowering bulbs that can be planted now include anemones, ranunculus and calla lilies. All three plus gladiolas, begonias and dahlias will freeze if left in the ground over winter. They should be dug in the fall in early October and stored in dry vermiculite in a cool, dark location.
Virtually all of these bulbs can be purchased as already growing plants in pots in May. However, the cost will be higher than if you buy them as bulbs.
Late April is also a good time to plant vegetables grown from roots or bulbs such as onion sets and asparagus.
Onions are hardy to frost. Potato tuber sprouts can be damaged by frost, but it takes about three weeks for them to emerge from the soil. So they can be planted in early to mid-May
This is also a good time to plant fruits like strawberries, raspberries, currants and bare-root fruit trees. Bare-root fruit plants are cheaper than potted plants, which will be available later. They also get a better start when the weather and soil are cooler.
Morning Briefing Newsletter
Get a rundown of the latest local and regional news every Mon-Fri morning.
