Sorghum Hydroponics

4/27

Today we plant sorghum seeds into flats – to be transplanted in 2-4 weeks from now. Background: we usually transplant about 2.5 acres of sorghum – about half of our crop. Why? We get much better plant population and weed control. Where do these transplants come from? We grow them ourselves: we plant seeds into individual cells in styrofoam flats. We fill the cells with a “soil medium” that consists of vermiculite, peat moss, bat guano, & worm castings: we plant 3 sorghum seeds in each cell by hand (this is truly a labor of love). We do a hundred of these flats (the math: 100 flats x 242 cells/flat = 24,200 cells x 3 seeds/cell = 72,600 seeds planted). Whew! I feel tired already!

But wait! I live on a commune – where “many hands make light work.” So how do we do it? Depending on how many people are here, it may take up to a week to plant all of them. At Sandhill, this is where agriculture and community intersect & meld – we are one of the few groups that combine organic/sustainable agriculture with homesteading skills and communal living. We often have college classes come for a tour and/or helping us with a work project. One of the most exciting groups to visit us for the last decade or so is a class from Knox College in Galesburg, IL that comes every second year. The class combines an experiment in communal living on a farm owned by the college during the spring semester. More than any other group, this class is aligned with our values and so we talk a lot about issues that come up in cooperative living, how to grow and preserve your own food, ecological issues in society and our lives, etc.

During this year’s visit, we planted most of the sorghum flats: when 20 people plant for 2 hours each – it’s not tedious and it gets done – over conversations about what really is sustainable/organic, and how do you deal with the issues of living communally? (Of course, we had to be prepared: purchase inputs, mix the medium, and fill the flats ahead of time so that when the students arrive, we can concentrate on putting seeds in the cells.) After they leave, I cover the seeds with a little more of the medium.

Then what? We put the seeded flats in a “pond”: a 12’ x 20’ structure of oak 2” x 8” boards (upright) on the ground with a plastic liner, filled with water. Arching over the top of this pond are aluminum pipe supports 2 – 3’ above the water. We stretch a heavy grade of remay-type material over the supports to create a mini greenhouse. The styro-foam flats float on the water in this pond for 2-4 weeks until transplanted. They do not need watering (they soak up water through the bottom of the cells) and there are enough nutrients to get the plants growing. The soil medium is light and fluffy so that it goes with the root mass during transplanting.

Transplanting: We transplant a cluster of 3 plants (one “plug” from each cell) every 2 feet in rows that are 38” apart – with a mechanical transplanter. The tractor pulls the transplanter, with 4 people riding it – 2 people per row. They take turns pulling a “plug” out of a flat and placing it between rubber fingers that hold it in place and are attached to a wheel which turns and inserts the plug into the ground. The planter then gives it a burst of water and firms the soil around the plants. Pretty nifty when it all works. Some things that make it less than ideal: the ground is cloddy and consequently, the soil is not pushed around the plants – so the transplants dry up before the roots get established; occasionally, one of the humans sticks the plug in upside down (rather humorous to see the roots sticking up in the air instead of the green leaves); too much or too little water, hot sun combined with drying winds that dry out plants, etc.