How to build a profitable fertigation system in a hoophouse

Seasonal demand, changing inputs, and availability of space are just a few factors that can change the growing and selling opportunities for farmers. Farmers ready to take advantage of those opportunities with different crops and grow methods are more successful overall. Fertigation is one method that can be used alongside other techniques. Compared to field crops, fertigation offers: 1) less evaporation from irrigation,2) less water loss from runoff, 3) higher yield, 4) better nutrient management

 

What is fertigation?
 

Fertigation is the precise application of nutrient solutions (fertilizers) through irrigation. In a contained system, fertigation is similar to run-to-waste hydroponics, where a solution is run once through the media. Instead of recirculating and being adjusted to the right EC and pH range, however, the leftover solution is drained. Farmers can redistribute the runoff water to other crops (Haydn uses it for his outside crops), but often there isn’t much runoff at all. 

 

In well-sized systems with good media, fertigation can be a perfect match to plant needs. Haydn runs his single pump on a timer to irrigate every two or three hours, depending on the time of season. Occasionally he gets a small puddle at the end of his irrigation system, but never more than a few gallons.

 

How does a farmer run fertigation?
 

Fertigation systems run in a system with media instead of soil and are essentially run-to-waste hydroponic systems; a solution concentrate is kept in a mixing tank (Haydn uses 50-gallon barrels for this) and injected into a sump tank with an injector, which mixes the solution to a certain EC. The maintenance for fertigation systems can be quite simple: Haydn mixes concentrate every 3-4 days, tops off the water when it starts to get low, and does walk-throughs a couple of times a day. Every now and then, a dripper is knocked from the pot or gets clogged. If he’s unlucky, a pump might burn out. Otherwise, system maintenance is largely preventative.