What is the Best Media choices for Hydroponic Greens Production? A visual guide to substrate trials at 14 and 21 days

First off, big thanks to Michael Evans, Department of Horticulture at The University of Arkansas for conducting the trial and providing the included pictures.

For this trial, Johnny’s seeds were used. The varieties chosen were “Rex” (Butterhead lettuce) and “Oscarde” (Oakleaf).

The Substrates used are:

  1. Smithers-Oasis
  2. Grow-Tech Flexiplugs
  3. Huntsman Foam
  4. Grodan Rockwool

First, we have both varieties at 14 days (“Rex” top, “Oscarde” bottom):

(Top Row- Rockwool AO 25/40, Rockwool AX 25/40, Huntsman Foam, Flexiplug, Bottom Row- Smithers-Oasis cubes)

Here are the same varieties at the 21 day mark:

(Top Row- Rockwool AO 25/40, Rockwool AX 25/40, Huntsman Foam, Flexiplug, Bottom Row- Smithers-Oasis cubes)

Below is additional data collected by Michael Evans:

What substrate do you think is the winner? What is your personal experience/opinion? Share in the comments below.