Transplant the seedlings from plug flats when leaves of adjacent seedlings begin to touch and root development is sufficient to remove the soil ball as a whole unit. Generally, three to four mature leaves will be present at the correct transplant stage. Water seedlings thoroughly immediately after transplanting. After transplanting, grow seed Impatiens at 62 to 65 degrees F night and 70 to 75 degrees F day temperatures. Use 65 degrees F night temperatures for a week or so after transplanting for rapid root development, and then drop to 62 degrees F if desired.
Lower temperatures delay growth and flowering.
Temperatures above 80 degrees F cause stem stretching and leaf damage, especially at high light intensities. Light No shading of the greenhouse glazing is necessary during the winter and early spring. However, greenhouse shading is needed as the season progresses. The fertility program should be adjusted according to the medium used, environmental conditions, watering practices, and stage of production. Adjust the fertilizer rate according to soil tests and foliar analysis.