September 2011 Culture

Crop Culture Report: Petchoa SuperCal Series By Mark Seguin

SuperCal, a revolutionary leader in the all-new flower class known as petchoa (petunia x calibrachoa hybrid) delivers the best characteristics of two top-selling species into one. From the petunia side of its family legacy, SuperCal inherits strong roots (which provide good pH tolerance and helps leaves stay greener under stressful conditions) excellent plant vigor, large flowers and ease of growing. Its calibrachoa heritage is evident with its intense, vibrant flower that hold up under severe weather and lush, non-sticky foliage that maintains a fresh, clean look without additional maintenance.

What really sets SuperCal apart, however, is its exceptional garden performance. SuperCal thrives under cool environments and conditioned plants can take temperatures in the upper 20s with no damage to the foliage. As the heat of summer rises and takes its toll on most cool-season annuals, you will find SuperCal outperforms traditional calibrachoa and petunias in its ability to maintain color and tolerate the higher temperatures.

Propagation Tips

Avoid applying too much mist in propagation as excess water slows rooting. Bottom heat enhances root development. Maintain soil temperatures between 68 and 72¡ F. Pinching SuperCal prior to transplanting is highly recommended to promote additional lateral branching. Growth regulator applications of daminozide (B-Nine) may also be applied to help prevent stretch.

Finishing Tips

Transplant rooted liners into a sterile, well-aerated mix. If not pinched during propagation, SuperCal should be pinched to four to five nodes shortly after transplanting. Optimum pH range is between 5.5 and 6.0, and EC levels should be maintained at 1.5 to 2.0 for best results. Delay feeding until roots are well established, and then begin with a complete, balanced fertilizer at 250- to 300-ppm nitrogen constant liquid feed (CLF). The use of Osmocote or other appropriate slow-release fertilizer products may be beneficial in supplementing a CLF program and may provide improved performance for the end consumer.

Extra iron may be applied to promote good leaf color. Apply iron sulfate drenches, (avoiding contact with the foliage), or iron chelate sprays or drenches. Provide periodic clear water applications if excess soluble salts accumulate. SuperCal are very early to flower (in central California they bloom in late February), but under low-light conditions they will benefit from supplemental lighting. Apply a preventative broad-spectrum fungicide drench seven to 10 days after transplanting.

Cool Growing

SuperCal is an ideal candidate for early spring production since they are less sensitive to day length and respond very well to cool temperature production (saving you energy costs as well). Once roots are established, night temperatures can be dropped to 50 to 55¡ F. Growing SuperCal cool is highly recommended since it helps develop a well-toned plant with shorter internodes and a dense, bushy habit without the need of PGRs. Adjust your production time accordingly, however, since you can expect a delay in flowering of seven to 10 days compared to finishing at 60¡ F. SuperCal will tolerate heavy frost, making it an excellent choice for growers with outdoor and/or cold-frame production as well.

Plant Growth Regulators

SuperCal tends to be quite vigorous and should be controlled by growing under cool conditions and high light or with PGR applications early in production. Plants respond well to foliar applications of daminozide at 2,500 to 5,000 ppm or paclobutrazol (Bonzi) at 20 to 30 ppm foliar spray or 2 to 3 ppm as a drench. Two to three applications may be required for finishing larger baskets and containers. To maintain optimum flower size, avoid spraying when flower buds are present and know that daminozide will change the flowers of 'SuperCal Terracotta' from orange to muted pink.

Pests & Diseases

SuperCal are susceptible to many of the same pests as calibrachoa. Monitor plants for aphids, thrips, leaf miners and fungal root rot and treat accordingly. Their non-sticky foliage provides for a cleaner look and helps minimize the potential of botrytis since spent flowers are more easily shed.

Crop Scheduling and Timing

Finish time for SuperCal will be influenced by light levels, photoperiod and temperature. Use the following chart as a guideline to assist you with production scheduling. Add 10 to 14 days to these production times if growing SuperCal under cool conditions as described above.

Variety Information

SuperCal features large 2-inch blooms and are currently available in eight striking colors. It should be noted that the veined colors (Terracotta and Vanilla Blush) tend to have a more upright habit, while the remaining six varieties are semi-trailing.