Hydroponically Grown Bearded Irises?

Original article courtesy of Maggie Asplet

In 2013, Ernie Lamont, one of the newer members of the Gisborne Iris Group, decided to try his luck growing irises hydroponically.  Knowing how little bearded irises like to have wet feet, many of the club members were skeptical about the experiment.  But Ernie had been successfully using hydroponics to grow vegetables and other plants for close to fifteen years, so if anyone could give a fair test to the technique, he would be the one. 

First year growth

Penny Ante blooming first year

Ernie's system is located in his greenhouse.  He uses materials anyone might have at hand:  old plastic or metal rain gutters and wooden troughs covered in plastic sheeting constitute the channels.  The pots and plants stand in a 50/50 mix of pumice and pea gravel about two to three inches deep.  The nutrient rich water is pumped up to one end of the channel and runs downhill into tanks which are low, forming a short waterfall, which puts oxygen back into the water.  The pump starts up every two hours and circulates the water for 15 minutes, then turns off, and the water drains back into the tank. 

After two years, the results of Ernie's experiment have been phenomenal.  Instead of rotting to death as many had feared, his irises have flourished along side of his vegetables.  The rhizomes are not covered with water; only the roots get flooded.  He has planted daffodil bulbs in the gravel as well, although he treats them as annuals.  He feeds the irises a weak nutrient solution all year and with boosts in the months required.

Maggie Asplet lives, gardens, and hybridizes irises in Gisborne, New Zealand.  She is the Webmistress for the New Zealand Iris Society and a member of her local iris society.  She began with just six irises from her mother's garden, and she currently grows over 1,000 varieties of TBs, IBs, BBs, SDBs, MDBs, Louisianas and species irises.

Ernie Lamont began growing hydroponic vegetables after tasting the results on a vacation to Norfolk Island.  He became involved in the iris world as a volunteer for his local iris society, setting up staging areas for iris shows.  His collection has expanded to 70 varieties, with 12 grown hydroponically.