Vegetative Petunia

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Cascadia™  Littletunia™  Ray

PROPAGATION

  • Avoid over application of mist in propagation. Too much water slows rooting.
  • For best results use a rooting hormone with up to 2500 ppm IBA. Mixtures that include up to 500 ppm NAA work well too.
  • Bottom heat enhances root development. Maintain soil temperatures between 70-75°F/ 21-24°C.
  • Growth regulator applications (B-Nine®) may be applied to prevent stretch.

CULTURAL REQUIREMENTS

Media

  • Sterile, well-aerated mixes are best.
  • Optimum pH range is between 5.5 and 6.0.
  • Consider that the water-holding capacity that is best for consumer performance may be greater than what is ideal for production.

Irrigation/Fertilization

  • Avoid excess irrigation when plants are young.
  • Feed with complete, balanced fertilizers at 250-350 ppm nitrogen (CLF). E.C. of 2.5-2.8 is a good target range under most conditions.
  • Provide complete minor element program.
  • Extra iron applications may be required to promote good leaf color. Apply as:
    Iron sulfate drenches (avoid contact foliage),
    or
    Iron chelate sprays or drenches
  • 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 consumer.
  • Provide periodic clear water applications if excess soluble salts accumulate.

Temperature/Humidity

  • Establish crop at 60°F/15°C average temperatures.
  • Once established, grow at:
    - 55-70°F/13-21°C day temperatures.
    - 55-60°F/13-15°C night temperatures.
  • For fast crop establish and grow at 68°F/20°C average temperature.
  • Low night temperatures encourage flowering.
  • Vegetative petunias respond to DIF regimes.
  • Provide good air circulation at all times.
  • Maintain relative humidity below 70% to prevent diseases like Botrytis gray mold.

Light

  • Bright light is ideal for this crop.
  • Provide a minimum of 5,000-6,000 foot candles/53,800-64,600 lux.
  • Vegetative petunias are long day responsive:
    - Natural flowering is late spring/summer.
    - Use of supplemental light (14-16 hours, beginning at midnight) is beneficial for early spring flowering.

Pinching

  • Pinch out growing tip 1-2 weeks after transplanting.
  • Light pruning to shape plants or correct for stretch can be done at any time but will delay flowering by 3-5 weeks.
  • Fast crop does not require pinching.

Plant Growth Regulators (PGRs)

  • Low light, warm temperatures and positive DIF cause stretching. Use high light, cool temperatures and a slight negative DIF for optimum growth control.
  • Vegetative petunias are responsive to PGRs, especially B-Nine® or Bonzi®. Petitunia® petunias may not require PGRs, while Cascadias®, Doubloon® and Marco Polo™ petunias may require one or more applications.
  • Avoid spraying when flower buds appear.
  • Use of PGRs can delay flowering 1-2 weeks.
  • Apply B-Nine at 1500 ppm 2-4 weeks after transplant (at least one week after pinch). Repeat applications as needed. Rates may be increased to 2500 ppm if more growth control is required.
  • In the warm Southeast region of the United States, Bonzi® drenches applied at 4 ppm three weeks after transplant work well. Lower rates should be used in other regions.

INSECT AND DISEASE CONCERNS

Insect
- Aphids
- Caterpillars
- Fungus gnats
- Leafminer
- Thrips
- Whitefly

Disease
- Botrytis (gray mold)
- Powdery mildew
- Root and stem rots
- Viruses

TROUBLESHOOTING

SYMPTOM: Yellowing of young leaves

POSSIBLE SOLUTIONS:

  • Check that fertilizer injectors are functioning properly.
  • Ensure pH of media is between 5.5-6.0. Adjust if outside this range.
  • Check iron levels in soil and tissue. Supplement with iron sulfate drenches if media pH is high or with iron chelate as a spray or drench if media pH is normal.

SYMPTOM: Yellowing of lower foliage

POSSIBLE SOLUTIONS:

  • Check that fertilizer injectors are functioning properly.
  • Check for low nitrogen levels in soil and tissue.
  • Check E.C. levels of soil for high salts.
  • Check magnesium levels in soil and tissue. If low, supplement with magnesium sulfate as a drench.
  • Check for root or stem rot.

SYMPTOM: Delayed flowering

POSSIBLE SOLUTIONS:

  • Supplement daylength if growing during short-day conditions of early spring. Use lights to provide 14-16 total hours of light.
  • Late applications of plant growth regulators can cause flower delay. Avoid treatment once buds are visible.

CROP SCHEDULING (REGULAR)

Season Container Size Cuttings per pot Weeks to Establish Total crop time weeks
Early Spring* 4” – 6” 1 1-2 7-11
Early Spring* 8”, 10”, 14″ 2-3 1-2 9-13
Early Spring* Hanging Baskets 2-3 1-2 9-13
Spring 4” – 6” 1 1-2 6-9
Spring 8”, 10”, 14″ 2-3 2-3 8-11
Spring Hanging Baskets 2-3 2-3 8-11

*Use of supplemental lighting is recommended for all early spring production.

CROP SCHEDULING (FAST CROP NO PINCH)

Season Container Size Cuttings per pot Total crop time (weeks)
Spring 4” – 6” 1-2 4-6
Spring 8”, 10”, 14” 3-5 6-8
Spring Hanging Baskets 3-5 6-8

We hope the information provided will be helpful. It is based upon data and knowledge (including information provided by the recipient) considered to be true and accurate, but without independent investigation and is offered for the recipient’s consideration, investigation and verification, but we do not warrant the results to be obtained. Please read all statement, recommendations, or suggestions in conjunction with any conditions of sale or use which apply to any products, or systems recommended by us. No statement, recommendation, or suggestion is intended for any use which would infringe any patent/copyright.

© 2011 Ecke Ranch

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