June 2014 Culture

Crop Culture Report: Sedum Touchdown Series

Sedum have come a long way. In the not-too-distant past, we had sedum ‘Autumn Joy’, which had many devotees, but had annoying habits, like falling apart. The Touchdown series of sedum redefine, “compact, yet upright, low habit” in the sedum arena. The Touchdown form is quite unique when compared to other varieties in the marketplace. With superior vigor and multiple crowns, they fill containers quickly, and don’t flop — the No. 1 complaint of growers and consumers. 

Gardeners demand a good color range and Terra Nova’s breeder complied with a full range from jade-blue through deep bronzy-red. Little fertilizer is needed, and pinching and PGRs are unnecessary with this group. Consumers also respond to the fact that sedums are one of the last plants that deer will eat due to their slippery, succulent texture. The gentle nature of the root system and the non-competing top-growth make these an ideal choice for container components, especially when paired with slow-growing grasses and daisy-shaped composites like dwarf echinacea or smaller coreopsis like ‘Citrine’.

Foliage colors change throughout the season adding additional interest and buyer-appeal. In the landscape, they are ideal plants for accents and low-borders, working very well along pathways and are best used en-masse.  

Terra Nova has announced this lineup of the Touchdown series of sedum:

‘Touchdown Breeze’. This, like the rest of the series, has a vigorous, multicrown, low habit that fills a container quickly. It has blue-green leaves in the spring that tint red-brown on the edges in the summer, matching its red stems. It has very large clusters of lovely pink flowers in late-summer. 

‘Touchdown Flame’. This variety is a multi-season beauty! In spring, flame-red leaves burst from the ground followed by deep red stems. In summer, the leaves are red-brown and olive-green, and then in late-summer, creamy yellow flowers cover the plant. 

‘Touchdown Jade’. This beauty carries blue-green leaves complemented by rose-red stems. Peachy-pink flowers in the late spring are followed by orange-colored seed heads in late summer.

‘Touchdown Teak’. This amazing plant boasts glossy red-brown to purple-brown leaves, red stems and a vigorous, upright-yet-low habit. Rose-red flowers are a summer feature. A favorite in our garden and a top-seller! 

Sedum Culture

Media. Sedums are succulent and prefer a well-drained media. Avoid mixes that are high in peat which can drown these plants.
Additional pumice or perlite can be added to existing mixes to lighten the substrate. 

Planting. Plant one 72-cell liner per 4-inch, quart or 1-gallon pot and two or three liners per pot for larger sizes. Make sure to plant the liner evenly with the final depth of soil in the pot (or slightly above, as soil settles) as these plants are quickly killed by burying the crown. 

pH/EC. These plants prefer a media pH of 5.5 to 6.5 and an EC of 0.5 to 1.0 via the pour-through method.  

Temperature. A 55 to 60° F nighttime air temperature and a 65 to 75° F daytime air temperature are ideal for sedums. Too high of growing temperature leads to soft, lush growth that is more susceptible to disease and prone to flopping over late in the season under the weight of its flower heads.

Light. Sedums need full sun to thrive. In partial shade, plants can become weak and floppy in addition to increased susceptibility to powdery mildew and downy mildew. Sedums are an obligate long-day plant and can be forced to flower by providing daylight extension. Avoid night interruption if possible as it can lead to stretching.

Air circulation. Good airflow and spacing between the plants is necessary. Dehumidification cycles (heat, then purge) can reduce the incidence of fungal pathogens in the greenhouse.

Fertilizer/watering. Supply plants with a low rate of constant liquid feed of 17-5-17 or 20-10-20 at 50- to 75-ppm nitrogen during active growth. Too much nitrogen will cause lush, soft growth that is more susceptible to disease. Dry the media out completely between watering, as root rot can be an issue if kept too wet. Avoid overhead irrigation when possible as leaf spotting can arise. Very little to no fertilizer is necessary in the garden.

Pinch/PGRs. Neither pinching nor PGRs are required to grow the Terra Nova sedums.  

Pests/disease. Aphids are the most common insect pest of sedums, but thrips are possible as well. Preventative neonicotinoid applications work well to keep these pests in check. In the northwest, the most common diseases of sedums are powdery mildew and downy mildew. These diseases can be mitigated by growing plants in full sun with good airflow. Preventative fungicide applications should be made, especially in greenhouse environments. Systemic fungicides such as 3336 and Eagle work well. Other fungicides include Heritage and Stature DM which also do a good job.

Scheduling. 72-cell liners work well in most containers, but 4-inch, quart and gallon sizes are most common. Growing a 72-cell to a 4-inch pot takes eight to 10 weeks and a gallon pot would finish in 10 to 12 weeks.

Overwintering. Vernalization is required for sedums to flower, and eight weeks at 45° F or below is sufficient. In the greenhouse, maintain plants as dry as possible during the winter. In the garden, ensure the plants have good drainage as a wet winter will kill this plant.