The Garden Decoder: What Is ‘Hydrozoning’?
Most people know that I’m a total plant nerd, but I’m also—not surprisingly—a word nerd. So, naturally, when I heard the word “hydrozone” for the first time, I tried to sleuth out the whole definition.
Photograph by Marta Xochilt Perez, from 10 Edible Garden Ideas to Steal from Michigan’s Favorite Foodie Farmers.
What is hydrozoning?
Simply put, it’s a water-conserving gardening method whereby plants are grouped by their water, soil, and light needs. By setting up hydrozones, you can fine-tune the amount of watering so that all the thirstier plants get more water than the drought-tolerant ones.
Why create hydrozones?
Photograph by Matthew Williams for Gardenista, from Ask the Expert: Roof Garden Basics with Designer Julie Farris.
When you incorporate the hydrozone concept into your design, you can create a lovely garden that is both sustainable and water-wise.
By managing your water and meeting the irrigation needs of each hydrozone, you can also encourage healthier plants that aren’t over- or under-watered (either can make plants susceptible to pests and disease.)
How do you create hydrozones?
Photograph by Justine Hand, from Garden Visit: A Revolutionary Landscape in Concord, MA
The general idea is that you group plants that have similar water and growing needs so that the irrigation can be set up as efficiently as possible.
Keep in mind these factors when figuring out your groupings: light requirements, water needs, soil conditions, temperature preferences, slopes and swales, and root depths of plants.
Ideally, every hydrozone should have a dedicated irrigation valve; the emitters in each zone should be spaced out and release the same amount of water to each plant in the zone.
Pro tip: Plant your water-loving plants near your high use area, where they can be enjoyed, and your more drought-tolerant plants near perimeters and underused areas.