Colorful calla lilies are beautiful, and worth a spot in the garden, even if it’s for only one season

In the Garden

Q: Do the calla lilies with colorful flowers need the same conditions as the ones with the white blossoms?

A: Calla lilies are natives of Africa renowned for their attractive foliage and beautiful spathe flowers.

The so-called common calla with the white flowers (Zantedeschia aethiopica) is semi-evergreen and can reach 4 feet tall, with large, solid-green leaves. In spring and early summer it produces a long stem topped with snow-white, funnel-shaped flowers of up to 8 inches. The common calla is practically indestructible. It can take sun or shade, and is hardy to 20 below zero. The one requirement is constantly moist soil. It can thrive for years, even in boggy conditions, but usually dies out in dry soil.

The callas with colored blossoms have different cultural requirements. These beauties add a tropical flair in beds and containers with arrow-shaped, heavily spotted leaves and gorgeous flowers that come in red, pink, yellow, gold, orange and purple.

They can handle full sun or light shade, but must have very well-drained soil to make it through our wet, rainy winters. Most varieties are only borderline hardy. If you want to keep them going, it’s best to dig and pot them up after the foliage dies back in fall, and store them dormant in an unheated garage, bringing them back outside in spring when temperatures warm up a bit after Mother’s Day.

Although some hybrids are purported to be hardy, I’ve tried leaving a few out in my Seattle garden, but the only one I’ve managed to overwinter successfully is Zantedeschia ‘Flame’. It’s a real stunner with golden-yellow flowers with red edges.

If you want to try overwintering your colorful flowering calla lily outdoors, remove the foliage after it dies back and cover the roots with a thick layer of evergreen fern fronds. The fronds not only provide insulation, they also repel excess water. To be honest, I don’t usually worry too much about trying to keep the colorful callas alive over winter. Any plant this spectacular wins a place in my garden, even if it lasts only one season.

Q: I noticed something was eating the leaves on my cabbage plants and found a number of small green worms. Where do they come from, and what is the best way to deal with them?

A: The caterpillars you discovered on your cabbage are commonly known as “imported cabbage worms.” The larvae are green with faint yellow stripes down their backs and sides.

Capable of reaching more than an inch long, these caterpillars are eating machines. They attack everything in the cabbage family, chewing large holes in the leaves of broccoli and Brussels sprouts, and are capable of boring right through a head of cabbage.

These voracious worms hatch from eggs laid by the cabbage moth. It’s the white butterfly that you’ve undoubtedly seen flitting around your vegetable garden.

The best way to prevent infestation is to cover cabbage family plants with floating row cover. Floating row cover is an extremely light, polyethylene fabric that allows light and water to penetrate, while keeping harmful insects out. Leave plenty of slack when you drape the material over the plants being protected to allow it to float up with expanding plant growth. Make sure to secure the edges with boards or bricks to prevent insects from entering under the fabric.

Because you already have imported cabbage worms in your crops, the best control at this stage is to search for and destroy the eggs and caterpillars. Look for yellow, cone-shaped eggs on the underside of the leaves and use your fingers to rub them off, while at the same time squishing caterpillars whenever you spot one.

Remember to hold the caterpillars as far away as possible when practicing “el Kabotski” pest control. The big ones make quite a splat!