Tag Archive | dahlia

Tender Bulbs from the Tropics

The plants known as summer bulbs are like spring bulbs in that they use a wide assortment of true bulbs, corms, rhizomes, and tubers for energy storage. But unlike spring bulbs, they are not frost hardy. Gardeners in temperate zones must plant them each spring and — if they don’t want to keep buying new ones — must also dig them up in fall and store them over the winter.

Glorious bed of gladioli

Although this didn’t bother the Victorians, who were big summer-bulb fans, over time these tender beauties gradually fell out of fashion. Fortunately, fashion is ever changing, and summer bulbs are again a hot item, with new introductions constantly entering the market.

The big four — which never really went away — are cannas, dahlias, gladiolus, and tuberous begonias, but they are just the start of a list that also includes acidanthera, sometimes called the peacock orchid (Gladiolus callianthus), which has tubular white flowers with a deep purple throat; the Mexican shell flower or tiger flower

Agapanthus

(Tigridia pavonia), whose iris-shaped, spotted flowers come in many

bright hues; the Peruvian daffodil or ismene (Hymenocallis narcissiflora), which has fragrant white or yellow daffodil-like blooms; and agapanthus, which has lush clusters of narrow leaves and starry clumps of blue or white flowers.

Want more? How about the bright yellow, orange, and orange-red wands of Crocosmia x crocosmiiflora and its several close relatives; the tall, fragrant, white-flowered Galtonia candicans, sometimes called summer hyacinth; and perhaps most fragrant of all, the tuberose (Polianthes tuberosa).

All these and more are easy to plant, easy to love, and readily available, but to be sure of the widest selection, consult specialty catalogs as well as your local garden center.

by OCMGA Master Gardener Vicki Schilleman

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Keep your Dahlias

dahlia-173799_960_720Dahlias will not winter over in places where the ground freezes, but they are easy to store if you have a cool place to keep them. Start by making labels while the plants are still blooming, so you remember which color is which. Wait until frost kills the top growth, then as soon as there is a dry day, cut off the dead foliage leaving stubs 2 inches long. Use a digging fork to lift the tubers; turn the clumps upside down.

Let the tubers dry a few hours, then gently remove as much soil as possible. Don’t wash them off, as the last thin layer of clinging soil will help protect them from shriveling. Line a large box with a plastic bag; then add a 4-inch layer of coconut fiber, dry shredded leaves, styrofoam packing peanuts, or sawdust. Place tubers stem side up on this bed, keeping them well separated. Nestle the labels into the clumps.

Completely surround the tubers with additional packing material, and loosely close the bag. Store in a dark place, ideally at 35º to 45ºF. When storage temperatures climb to the mid 50s, the tubers will start sprouting. Ignore short sprouts; they’ll be buried when you plant. Clumps that come from storage with long, pale stems, however, should be hardened off before being set out into the garden.

Dahlia tubers

Dahlia tubers

In the spring, as long as there are a couple of healthy-looking eyes (the buds from which the plants grow, located up near the old stem), even rather shriveled tubers will make decent-size plants. If shoots have started to grow, evaluate them before planting. If they are still small (less that 2 inches long), just bury the tubers as you would normally, a couple of inches below the soil.

If the shoots are long and pale, they will be too far along to bury completely; they’ll also be brittle and vulnerable to sunscald, so handle carefully. Toughen up the shoots by putting the tubers with their new growth in the shade for a week or so before planting. Plant the tubers at the normal depth, with the long shoots above ground, and continue to protect the shoots with a light sprinkling of straw for the next week or 10 days. The idea is simply to shade the bleached growth until it turns green, so don’t smother it with a heavy layer of mulch.