Best way is to use a Mixrite 571CW injection pump. Hook it right up to your irrigation system after the backflow per instructions. Be sure to buy the 75-11-1 Tip Kit, This will allow you to dilute the concentrated fertilizer with ratios of 750:1, 1000:1, 1500:1, or 2000:1.

Works perfectly, and with these low ratios you can leave the injector permanently on and you'll have micro fertigation, which plants really like. Only drawback: Even though the pump is non-electric, it is very loud. I had to build an insulated box around mine.

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