New Guinea Impatiens

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Paradise®, Painted Paradise®, & Pure Beauty


New Guinea Impatiens (NGI) are relatively easy to propagate. Providing the appropriate cultural conditions is the key to successful root system development. In North America, most NGIs are propagated during late fall and early winter when light intensities are low enough that additional shade is not required. These same low light, cool temperature conditions impact the speed of rooting and create conditions favorable to insects or diseases that may attack the crop. Starting with good quality cuttings from reliable suppliers is your best defense for preventing problems. Propagation Cycle: 4 weeks


  • Choose a well-drained aerated propagation media
  • Avoid media containing peat moss which will hold too much water
  • Choose a blended media with other components or inorganic media such as Oasis® or Rockwool®

Bottom Heat

  • Bottom heat will promote healthy root development.
  • Maintain bottom heat at 70-75°F/21-24°C.
  • Mist will cool the media temperature. Monitor media temperature closely and frequently.

Rooting Hormones

  • Most cultivars root easily without the use of rooting hormone, however some more difficult cultivars to root will benefit from the use of a rooting hormone.
  • Either liquid or powder formulations work equally well. Use suggested rates for most herbaceous plants

Temperature Management

  • NGIs prefer a warm propagation environment. Maintain day temperatures of 70-80°F/21-26°C and night temperatures of 68-72°F/20-22°C.


  • Mist cuttings so they remain turgid but avoid over misting that results in saturated media.
  • Over misting will result in slow rooting and possible problems with root rot and botrytis.

Growing On

Choose a media with the following traits:

  • Good aeration
  • Porosity between 5-15%
  • Sterile
  • Contains about 50% peat moss

Irrigation /Fertilization

  • Avoid excess irrigation and fertilization while plants are establishing which can lead to slow root development. Once plants have established do not allow to dry excessively which will result in damage to foliage and flowers.
  • Fertilizer Regime
    • Begin fertilizing 2-3 weeks after transplant.
    • Choose a complete balanced fertilizer complete with minor elements. Avoid fertilizers with elevated levels of minor elements which may cause damage.
    • A periodic feeding of 100-150 ppm constant liquid feed.
    • During active growth, fertilizer levels may be increased to 200 ppm nitrogen
  • Maintain pH between 6.0-6.3
  • Optimum EC is below 2.0 mmhos. Provide periodic clear water application if excess salts accumulate.


Establishing temperature:

  • 70-80°F/21-26°C day temperatures.
  • 68-72°F/20-22°C night temperatures

Temperatures for growing on:

  • 70-80°F/21-26°C day temperatures are optimum.
  • 60-65°F/15-18°C night temperatures encourage flowering.

Relative Humidity:
Maintain relative humidity below 70% and provide good air circulation to avoid problems with botrytis.

Establish crop with as much light as possible.

  • 5000 foot candles/53,800 lux minimum
  • 6000 foot candles/64,600 lux maximum

*As increasing day length and light intensities during the spring cause elevated greenhouse temperatures, shading may be required, especially in warmer areas of the country.

Establish plants pot tight than space to:

  • 4” pots – 5-6” centers (approximately 2 per sq. ft.)
  • 6” pots/1 gallon – 14” centers
  • 8” pots – 18” centers

* Pinching is not recommended. Pinching will remove the center bud and add 3-4 weeks to the crop cycle.

Plant Growth Regulators
Growth regulating is generally not necessary on New Guinea Impatiens. Good cultural practices, adequate light levels, and low use of ammoniacal nitrogen fertilizers will all prevent stretch. Overcrowding and hanging baskets overhead will also cause stretch. Spaces plants adequately and avoid hanging baskets over the crop. Use of a negative DIF or a cool morning drop is generally effective in controlling height. If needed, research has shown that Bonzi® is the most effective at controlling stretch. Follow recommended rates on the label and trial rates for maximum effectiveness.

Insect and Disease Concerns

  • Aphids
  • Fungus Gnats
  • Spider Mites
  • Thrips


  • Botrytis
  • Myrothecium
  • Powdery Mildew
  • Root and stem rots

Monitor the NGIs and any adjacent crops for insect pests. During the winter months, most outdoor pests are easily controlled and rarely pose a threat to the crop. Check incoming plant material for pests and diseases that might attack NGIs.


Product form # of cuttings
per pot
Weeks to finish
Jan-Feb Mar-April
4″ pot 1/pot 6-8 5-7
8-10” basket 1/pot 9-10 7-9
8-10” basket 3-4/pot 10-12 9-11
8-10” basket 4-5/pot 10-12 9-11

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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