Getting the Timing Right Is the Key for Configure® Foliar Sprays on Increasing Flower Number of Christmas Cactus

Brian Whipker, North Carolina State University

I received a number of questions pertaining to the timing of Configure® foliar sprays on Christmas cactus (Schlumbergera bridgesii). The active ingredient in Configure® is benzyladenine, and extensive research at North Carolina State University and elsewhere has proven the benefit of its use to increase the flowering of Christmas cactus (figure 1). A review of the best management practices for use of Configure® will help answer those questions as we near the time to apply it to improve flowering.

Tips for Increasing Flower Bud Number:

Timing of application is critical to achieve the desired effect. Apply Configure® after the start of short days to stimulate an increase of flower bud production. The floral initiation period in Christmas cactus begins under short day conditions (around September 21 in the northern hemisphere).

Optimally, short day conditions are achieved with exact control of the long day and short day photoperiods. The time to apply Configure® is one week after floral initiation begins when using black cloth.

Most growers rely upon the natural season day length to induce flowering. This requires that you observe the crop to determine when the optimal application period should be. If relying upon natural season day length conditions, apply Configure® within 2 days after the first flower buds are just visibly emerging from the phylloclades (figure 2). This occurs in early October. Gently feel the end of the phylloclades for a slight enlargement (figure 3). This lets you know a flower bud will emerge soon.  Based on our trials from last year at North Carolina State University, flower bud emergence occurred around the 10th of October. 

A single foliar spray application of 100 to 200 ppm Configure® is ideal for increasing the number of flowers on most Christmas cactus cultivars. If you have never used Configure®, consider starting your initial trials with the rate of 100 ppm. Growers have reported that lower rates of 50 ppm may be effective on some white cultivars. Concentrations of 400 ppm or greater can result in the production of an excessive number of small flower buds and many of these may not fully flower (figure 4).

Apply Configure® only after the plant has begun flower initiation. Applications made in late September while the plants are still vegetative will stimulate additional phylloclades instead of flower buds (figure 5). This will result in plants with fewer flowers.

Complete spray coverage is required, especially for pots containing multiple cuttings. Configure is not actively transported by the phloem within the plant. Therefore if a portion of the plant is not sprayed, Configure® will not move there in the phloem to stimulate additional flower buds.

Conclusions

Overall, Configure® foliar sprays applied to Christmas cactus are an excellent method of increasing both the number of phylloclades and flower buds being produced. This will enable you to produce top-quality plants that consumers will enjoy. So consider conducting your own Configure® trial on Christmas cactus to see how your flower power can be increased.

Configure® Use Guide
http://www.greenhousegrower.com/production/crop-inputs/pgrs/fine-americas-releases-new-configure-guide/

Figure 1. Comparison of bud count on an untreated plant (left) and one sprayed with Configure® at 100 ppm (right).

Figure 2. Apply Configure® within 2 days of the emergence of the flower bud.

 

Figure 3. Gently feeling the phylloclade for a slight enlargement lets you know that the flower bud will be emerging in the next few days.

Figure 4. Excessive rates will result in an abundance of flower buds being produced. Unfortunately, not all of these flower buds will open. Keep good notes on the cultivar response to Configure® and adjust rates as needed.

Figure 5. Applications made before the plants are reproductive will result in the stimulation of additional non-flowering phylloclades, at the expense of flower buds. All Configure® should be applied after the plants are reproductive, which means either 1 week after the start of short days if using black cloth or within 2 days of when flower buds emerge from the phylloclade.