Growing instructions for Iris

Receipt and inspection of Iris bulbs
Check the bulbs for:

  • Root development
  • Proper bulb size
  • Proper quantity
  • Pennicillium or other bacterial/ fungus growth

Best soil type for Iris
Iris can be grown in several soil types, from a heavier clay soil to sandy soil. Obviously a sandy soil is easier to cultivate.

Fertilizer requirements for Iris
Iris can be grown easily with a slow release fertilizer or a basic fertilizer mix

  • pH: 6 to 6.5
  • EC: 1.3
  • N : 4.0
  • P : 0.1
  • K : 1.5
  • Mg: 1.3
  • Ca: 2.0
  • Fe: 48.0 to 10.0
  • B: 15 to 20

Planting the Iris bulbs
Dip the bulbs in a fungicide dip for about 20 minutes prior to planting. Rotate the soil well so it is all loose and can drain well. Push the bulbs in by hand. About a 0.5 inch deep with the roots down and tip up. Plant about 12 to 15 bulbs per Sq Ft. When plant, be sure that the soil is moist.

Irrigation Iris crop
Water right away after planting. Iris likes to be kept moist at all times. They root fairly deep but need moisture and even more so going into spring and summertime. If you stay on the dry side, your crop will stay short. Overhead watering seems to work the best but be sure that you irrigate early mornings.

Greenhouse climate for Iris bulbs
Most Irises are grown outdoors in the field. Field grown Iris are growing slower and therefore produce a more heavy quality. When growing indoors be sure that they get enough spacing since Iris can go blind easily. An Iris is very light sensitive. If they are grown in a greenhouse in wintertime and it has been dark weather you can experience dried up flowers which is due to dark weather. Also be sure to use a large enough bulb size and the right varieties for indoor production, this also counts for pot production. Certain varieties will not get as tall and will have wider leaves that suits pot production much better.

Iris crop protection
We already mentioned to dip the bulbs in a fungicide before planting. During the crop especially outside grown, iris needs to get a fungicide spray weekly or every 10 day's. Botrytis is a disease that will strike if you do not have a preventative spray program. At times you might endure Aphids but Botrytis is your main disease to look out for. Fusarium is a disease that affects many iris crops. Be sure to plant the bulbs in disinfected soil (Basamid, Steamed soil or methyl Bromide) Best Iris crops we have seen in virgin soil or with crop rotations of 4 to 5 years.

Harvesting Iris flowers
Every 1 to 2 days, Iris is being harvested. In summertime when it is warm you almost have to pick twice a day. Try to do this early in the morning before it starting to get warm. Get the flowers into water and into the cooler as soon as possible. Certain companies have ice machines and when they harvest the flowers the Iris will go into Ice water and straight into the cooler. Strip some of the leaves and bunch in 10 stem bunches. Do this in the bed. Be sure that the buckets are clean. Iris can be dried stored for up to a week. However they need to be in water first for a day before you can dry store them.

Flamingo Holland cannot be liable for any loss of profit, growing result or any other commercial damages resulting from use of this guide. This guide is for information purposes only and are not warranted for content, accuracy, or performance overall. 

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