How to Help Late-Season Poinsettias Get More Height

Just about every year around Week 40, Ball Seed gets calls from growers with poinsettias that are still on the small side, with many concerned they won’t hit their goals. While getting close to Thanksgiving-time ship dates, there’s still time to push some additional growth in poinsettia crops. Here are a few methods for getting poinsettias to fill out quickly and still have enough time to tone them before they ship and/or hit retail benches.

Height Help for Late-Season Poinsettias

Because of the plant structure, growers shouldn’t want to encourage overly lush growth that could risk burying developing cyathia below the canopy. So, how much height do you need to add to the crop, and how much time do you actually have to do so? Always reserve the last approximately two weeks (at least) in the crop cycle to cool air temps and promote good tone.

• If the crop only needs a gentle nudge (about 3 to 4 inches in height), growers can likely make up the size needed by slightly increasing air temps, DIF (difference between day and night temperature), fertilizer, and/or watering a little heavier.
• If the plants need to put on a significant amount of height (6 inches or more), use of plant growth regulators (PGRs) containing gibberellic acid (GA) will be the best insurance policy.
• Drench applications of Fresco (Fascination is not labeled for drench) will enhance growth evenly across the plant, whereas sprays have a more localized effect at the spray site.
• Rate and number of applications needed will vary by region and cultivar, but a 2 ppm drench is a good starting point for many growers.
• Consistent application volume across the crop is key. Apply 1 fl. oz. per inch of container diameter plus 1 fl. oz. per additional cutting to each pot.
• Keep in mind that late foliar application may impact plant height. Test a few rates on different cultivars before applying to the whole crop.

For more in-depth instructional information on adding additional height to poinsettias, including practices for increasing bract size instead of height, read the full Technical Services blog on the Ball Seed website.