September 2004

Sedum spurium‘Voodoo’ By Paul Pilon

Sedum 'Voodoo' offers perennial producers great versatility with their marketing strategies, as this perennial can be used in numerous ways. Its branching habit, combined with its intense red leaf color forms an aesthetically pleasing potted plant or a dense carpet of dark leaves in the landscape. Voodoo offers the ability to be used as a specimen plant or in mass plantings. Growers are utilizing it alone in containers or as a component in combination plantings. Sedum spurium cultivars also make great additions to rock and rooftop gardens.

Voodoo thrives in sunny locations throughout USDA Hardiness Zones 3-9 with AHS Heat Zones 3-8. This durable, drought-tolerant ground cover bears bright neon rose-colored flowers on 3-inch-tall stems from June to August in most locations. With its growing habit and ease of production, it earned the Fleuroselect Quality Mark in 2003, which identified Voodoo as one of the best new introductions of that year.

Propagation

Voodoo is propagated from seed. To improve the overall appearance of the finished product and to slightly reduce the crop's production time, growers generally sow multiple seeds per cell or pot. Most greenhouses sow the seed in 288- or 200-cell plug trays filled with a growing medium that provides good aeration. Providing light during germination will improve the germination rate and uniformity of emergence. During this stage avoid excessive moisture and humidity. Germination takes 10-14 days at temperatures between 64 and 72¼ F.

Once germinated, continue maintaining temperatures between 62 and 72¡ F and gradually lower the humidity. After the true leaves are present, temperatures can be lowered to 58-64¼ F. At these temperatures, Voodoo will finish the plug stage in approximately 6-8 weeks. During the plug stage it is important to keep the media uniformly moist but not wet.

Production

For best performance, plant Voodoo in a well-drained media, preferably a nursery-type mix (bark based) rather than traditional greenhouse (peat-vermiculite) media. Not only is the porosity (drainage) of the media beneficial during crop production, it is essential to successfully over-winter this variety of sedum, as it does not tolerate wet soils for long durations. The pH of the media should be maintained between 6.0 and 6.5. Voodoo is a light to moderate feeder, requiring a controlled-release fertilizer incorporated at a rate ç equivalent to 1 lb. of nitrogen per yard of growing medium or 75-125 ppm nitrate delivered under a constant liquid fertilizer program.

Voodoo requires a below-average amount of irrigation; it is a succulent plant and can tolerate average watering regimes but generally performs best under slightly dry conditions. I recommend, when watering is required, to water thoroughly and allow the substrate to dry between waterings. Keeping it on the dry side will help reduce plant stretch and intensifies the color of the leaves and stems.

Scheduling

Voodoo can be marketed either as a flowering or non-flowering plant. To sell as a non-flowering plant with awesome foliage appeal growers can easily produce it in packs, small pots or even 1-gal. containers. Non-flowering Voodoo can be sold throughout the growing season from spring to fall. Flowering sedum is usually available from early spring to mid-summer and produced in 4-inch or larger containers.

After transplanting from a small plug, you can expect Voodoo to take 6-8 weeks to finish a non-flowering 1-quart container when providing temperatures of 60-65¼ F. At these temperatures a non-flowering 1-gal. container would take approximately 10 weeks. When it is grown at warmer temperatures, Voodoo grows more rapidly, and the stems become softer and have a lush appearance.

To produce flowering plants it is best to provide vernalization either to the plug or in the finished container. Sedums should be exposed to a minimum of 10 weeks of temperatures below 44¼ F to complete vernalization. When providing a cold treatment to plugs, I would recommend treating them in a 72- or larger cell size to reduce the likelihood of plant losses during this stage. When over-wintering Voodoo in finished containers, such as a 1-gal., be sure to plant it in mid to late summer to allow enough time to become established prior to receiving any cold.

After the cold treatment, Voodoo can be forced into bloom by providing long-day conditions. Growers can create long-day conditions by extending the day length or providing night interruption; both methods involve the use of supplemental lighting. Day length extension involves extending the naturally occurring short days to long days by lighting for the desired length of time. For example, if a grower is trying to achieve a 14-hour day length during a time of year when natural day length is only 10 hours, they would provide lighting from about an hour before dusk up to the time the plant has received 14 hours of light. Night interruption is accomplished by lighting continuously from 10 p.m. to 2 a.m., which causes the plants to perceive long days and promotes flowering. With either method of creating long days, Voodoo will flower in 10-12 weeks from the onset of long-day conditions when it is grown at 60-65¼ F following the cold treatment.

Pests/Diseases

Voodoo, like most cultivars of sedums, does not have many insect pests. Various species of aphids seem to be the most prevalent insect to feed on sedum. Aphids can be easily controlled with various chemicals as soon as they are detected. I have had great success using insecticidal soaps combined with various pyrethroids such as Decathlon (Olympic Horticultural Products) or Talstar (FMC Corp.). Another excellent option would be a preventative application of Marathon 60WP (Olympic Horticultural Products) as a drench to provide season-long control of aphids.

Availability

Voodoo is available as seed from Ernst Benary of America, contact your sales representative or visit www.benary.com. Plugs or finished containers are produced and can be obtained from many reputable companies across the country.