What Are Grow Trays & Flood Tables?
A grow tray, also called a flood table, holds plants and grow media above a reservoir in an ebb and flow or drain-to-waste system. Channeled tray bottoms flood evenly during a watering cycle, then drain completely so plants never sit in standing water - keeping both root zones and grow room humidity easier to manage.
Trays are sized in one of two ways: inside dimension (ID), which measures the usable interior planting area, or outside dimension (OD), which measures the tray's outer footprint. ID trays typically sit on top of a frame; OD trays are built to drop into or sit flush with a same-size stand. Always check a tray's spec sheet against your stand or bench frame before ordering.
Choosing the Right Tray for Your Bench
2' x 4' and 4' x 8' trays are the most common sizes in indoor growing, pairing directly with standard light footprints - a 4' x 8' bench typically sits under two 4' x 4' fixtures. Trays work equally well on a fixed tray stand or a rolling commercial bench; for larger rooms, PIPP Horticulture, NextG3N, and CM Horticulture also build engineered benches with integrated ebb and flow trays to custom widths and lengths.
What is the difference between an ID and OD grow tray?
ID trays are measured by their inside, usable planting area and typically sit on top of a stand. OD trays are measured by their outer footprint and are built to drop into or sit flush with a same-size frame.
What size grow tray should I buy?
2' x 4' and 4' x 8' are the most common sizes and pair directly with standard grow light footprints. Match the tray to your available bench or stand dimensions before ordering.
Can grow trays be used with rolling benches?
Yes. Ebb and flow trays are a standard bench top option on rolling and tracked benches, including engineered systems from PIPP, NextG3N, and CM Horticulture that integrate the trays directly into the bench frame.
How does ebb and flow irrigation work in a grow tray?
A pump floods the tray with nutrient solution on a timer, then the solution drains completely back to the reservoir. This keeps the root zone from sitting in standing water between cycles.
Do rack trays work the same way as standard grow trays?
Rack trays are a shallower-wall version built for multi-tier and vertical rack applications, while standard grow trays have deeper walls suited to single-level benches and stands.
Questions on sizing a tray to your bench or stand? Call 888-815-9763. Fast shipping on most orders.
