October 2011 Culture

Nepeta nervosa ‘Pink Cat’ By Paul Pilon

Nepeta nervosa 'Pink Cat' offers growers many desirable attributes such as a compact growing habit, an extended bloom time, and ease of production. This attractive and fragrant bloomer also has strong landscape performance, which has helped it become a Fleuroselect Quality Award Winner.

'Pink Cat' forms compact mounds of dark-green foliage and produces numerous clusters of large, hot-pink flower stalks in the mid summer. Its appearance is more similar to stachys moineri than the nepeta cultivars most growers are familiar with. At maturity, the dense clumps produce foliage that grows 4 to 6 inches tall by 10 to 12 inches wide; the plants reach 9 to 11 inches in height when in bloom. To encourage a second flush of flowers, the plants can be cut back after blooming.

Catmint performs well across much of USDA Hardiness Zones 4 to 9 and AHS Heat Zones 9 to 3 where they prefer to be grown under full sun to partial shade. Nepeta can be grown in dry soils and is heat tolerant. In the landscape, nepeta 'Pink Cat' attracts butterflies and hummingbirds into the gardens and is resistant to rabbit and deer feeding. 'Pink Cat' is commonly used in edge plantings or near the front of perennial borders and due to its compact size and prolific bloom; it makes a great container plant and cut flower. With its tidy growing habit, first year flowering, and ease of production, nepeta 'Pink Cat' has great potential for commercial growers.

Propagation

Nepeta 'Pink Cat' is propagated from seed. Growers commonly sow three to four seeds per cell in 288- to 128-cell plug trays. Cover the seeds lightly with germination mix or medium grade vermiculite to help keep the seed moist during germination. The seed flats should be moistened and moved to a warm environment, where the temperatures can be maintained at 65 to 68¡ F for germination. To improve germination, many growers utilize germination chambers to provide uniform temperatures and moisture levels. It takes five to 10 days for the seeds to germinate.

Following germination, reduce the moisture levels somewhat, allowing the growing medium to dry out slightly before watering to help promote rooting. Continue to maintain growing temperatures at 65 to 68¡ F following germination. Fertilizers can be applied once the cotyledons are fully expanded, applying 100- to 150-ppm nitrogen every third irrigation or 75 ppm with every irrigation, using a balanced water-soluble source. When plugs are grown at 65¡ F, they are usually ready for transplanting in six to seven weeks.

Production

Nepeta 'Pink Cat' is suitable for production in 1-gallon or smaller sized containers. Growers commonly use a single plug transplanted into small container sizes or when fall planting large container sizes. When spring planting fresh or vernalized plugs, I recommend growers transplant two plugs per 1-gallon container to help fill out the container prior to flowering. When transplanting, the growing medium should be even with the top of the plug.

Catmint performs best when grown in a moist, well drained medium with a slightly acidic pH: 5.8 to 6.4. Most commercially available peat- or bark-based growing mixes work well, provided there is adequate drainage. They require an average amount of irrigation; keep them moist, but not consistently wet. When irrigation is necessary, water them thoroughly then allow the soil to dry slightly between waterings.

They are light to moderate feeders. Nutrients can be delivered using water-soluble or controlled-release fertilizers. Growers using water-soluble fertilizers, apply 75- to 100-ppm nitrogen with every irrigation or use 200 ppm as needed. Controlled-release fertilizers can be incorporated at a rate equivalent to 1.0 pounds of elemental nitrogen per yard of growing medium or top dressed using a rate between the low and medium top dress application recommendations located on the fertilizers label.

With their compact growth habit, it is usually not necessary to control the plant height. However, during periods of low light levels, when grown at high plant densities, or when grown with luxury nutrient levels, an undesirable amount of stem elongation is likely to occur requiring some type of height management strategy. Plant height can often be controlled by providing adequate spacing between the plants. If additional height control is necessary, spray applications of paclobutrazol (Bonzi, Paczol or Piccolo) at 30 ppm or daminozide (B-Nine or Dazide) at 2,500 ppm are effective. Applying one to two applications seven days apart should provide adequate height control.

Insects and Diseases

Aphids, leafhoppers, slugs, spider mites and whiteflies may occasionally be found feeding on nepeta. The primary diseases likely to infect them are powdery mildew and root rots (including Thielaviopsis). These insects and diseases can be detected with routine crop monitoring; control strategies may not be necessary unless the scouting activities indicate actions should be taken.

Forcing

One of the most appealing characteristics of nepeta 'Pink Cat' is its ability to bloom profusely the first year from seed. Vernalization is not required for flowering. However, growers can still grow them as a traditional perennial by planting them in the late summer or use vernalized liners for spring planting. Nepeta are long day plants that require long photoperiods (14-hour day lengths) for them to flower. When the day length is naturally short, long day conditions can be created by providing photoperiodic lighting for 14 to 16 hours by extending the day or using a four-hour night interruption during the middle of the night, providing a minimum of 10 foot-candles of light at plant level.

The time to flower after the proper photoperiod is provided is a function of temperature. 'Pink Cat' grown at 65¡ F will take approximately eight weeks to reach flowering, while plants grown at 60¡ F will flower in about 10 weeks. Producing them at cooler temperatures increases the time to flower, but will improve the overall quality characteristics of the plant, such as the color intensity of the foliage and flowers.

Availability

Nepeta nervosa 'Pink Cat' was brought to the market by Kieft-Pro-Seeds (www.kieft-pro-seeds.com). To obtain seed, contact your Ball sales representative (www.ballhort.com). Plug flats can also be obtained through your Ball sales representative or various reputable perennial plug producers.