AutoPot Garden Trays – 3.3’ x 3.3’ Square

The AutoPot Garden Tray in the 3.3′ x 3.3′ Square size is the largest tray in the AutoPot garden tray range. Measuring 39.5″ long by 39.5″ wide by 5″ high and constructed from injection-molded recycled polypropylene, it offers a 26-gallon internal capacity and a series of shallow ridges on the internal base that promote drainage away from plant pots. It is suitable for hydroponic growing setups, drip and spillage containment in commercial settings, and a range of other applications where a large, robust, chemical-resistant tray is needed.

AutoPot 3.3′ x 3.3′ Square Garden Tray Specifications

All dimensions and capacities below are drawn from manufacturer documentation for the 3.3′ x 3.3′ variant. Verify footprint clearances before installation.

Why Choose the AutoPot 3.3′ x 3.3′ Square Garden Tray

This tray occupies a specific niche in the AutoPot range: it is the single largest square tray available, and at 5″ deep with a 26-gallon capacity it handles volumes and footprints that smaller trays simply cannot. The following points explain what sets it apart from more compact options.

• Largest in the AutoPot range. The 3.3′ x 3.3′ tray is explicitly the biggest square tray AutoPot produces. If you are working with larger pot diameters or need to cover more grow-space area in a single tray, there is no larger square option in the lineup.
• 5-inch sidewall depth. At 5″ deep, this tray holds substantially more runoff or solution than shallower trays. This is relevant in high-volume drip systems and during extended reservoir cycles where liquid accumulation between drainage intervals would overflow a shallower tray.
• 26-gallon internal capacity. The 26-gallon volume is not incidental – it means the tray can absorb a significant amount of liquid before it needs to be drained. In commercial spillage containment contexts (oils, nutrient solutions, chemicals), this capacity can prevent floor contamination during a full-system flush or an accidental overflow event.
• Internal base ridges. The shallow horizontal ridges molded into the tray floor elevate the base of plant pots slightly above any pooled liquid. This allows excess water and nutrient solution to drain away from the root zone and collect at the bottom of the tray without sitting directly in contact with the pot base over long periods.
• Recycled polypropylene construction. Polypropylene is chemically resistant to most nutrient solutions, pH adjusters, and cleaning agents used in hydroponic environments. Using recycled material keeps the product specification environmentally considered without compromising structural performance.
• Multi-purpose footprint. The same structural qualities that make this tray useful in grow rooms – large volume, rigid walls, chemical resistance – make it suitable for non-horticultural applications: cement mixing, industrial drip trays, display trays for garden centres, and similar uses where a large, sturdy containment vessel is needed.

Best Uses for the AutoPot 3.3′ x 3.3′ Square Garden Tray

The 3.3′ x 3.3′ tray works across several use contexts. The primary use is hydroponic and greenhouse growing, but its construction supports a range of other applications.

• AutoPot and gravity-fed hydroponic systems. This tray pairs naturally with AutoPot modules and AQUAvalve-based setups where pots sit in a tray that periodically fills with nutrient solution. The internal ridges allow solution to sit below the pot base, keeping roots in the correct wet-dry cycle. If you are running an air-assisted reservoir system alongside a gravity-fed AutoPot layout, this tray provides the catchment area for a cluster of larger pots.
• Large-pot drip irrigation catchment. In recirculating drip systems where pots run 5-gallon and above, runoff volume per feed cycle can be substantial. The 26-gallon capacity means the tray can catch the full runoff from several large pots across a feed event before drainage is required, reducing the frequency of manual intervention.
• Commercial spillage and drip containment. The tray functions as an industrial-grade secondary containment vessel for nutrient concentrates, pH solutions, and cleaning chemicals in storage areas. Its chemical resistance and rigid walls make it appropriate for environments where floor-level spill containment is a practical or regulatory requirement.
• Propagation staging. The large flat footprint can support multiple propagation trays, humidity domes, or seedling flats during the early stages of a crop cycle, providing a unified catchment surface for irrigation runoff during propagation.
• Non-horticultural applications. The manufacturer notes use as a sandbox, display tray for garden centres, and cement-mixing tray. These applications benefit from the same properties relevant to growers: large volume, rigid structure, and material resistance to moisture and many chemicals.

Compatibility

The AutoPot 3.3′ x 3.3′ Square Garden Tray is a passive containment vessel with no electrical components, pumps, or fittings, so compatibility questions center on physical dimensions, system design, and the materials in contact with the tray.

• AutoPot 1Pot and modular systems. The tray is sized to work as a catchment base for AutoPot module arrays. Confirm individual module footprints and spacing against the 39.5″ x 39.5″ internal measurement before configuring a multi-pot layout.
• Pot sizes. The 5″ sidewall depth accommodates standard round and square pots without the pot rim hanging over the tray edge, provided the pot diameter is within the tray footprint. Verify the outer pot diameter against the 39.5″ internal dimension.
• Nutrient solutions and pH adjusters. Polypropylene is chemically resistant to the nutrient solutions, pH-up and pH-down products, and hydrogen peroxide-based cleaning solutions typically used in hydroponic environments. If you are monitoring EC levels with a tool like the Apera GroStar EC electrode, the tray will not contaminate readings through leaching.
• Water quality requirements. This tray has no water quality requirements of its own. However, growers using it in gravity-fed systems that benefit from low-TDS input water may find it useful alongside a reverse osmosis filtration system to ensure consistent baseline water quality entering the AutoPot reservoir.
• Floor and staging surfaces. The tray bottom is flat and designed to sit on level surfaces. Greenhouse benching, concrete slab floors, and greenhouse staging are all appropriate substrates. Avoid placing the tray on surfaces that are not level, as solution pooling will be uneven and may not drain correctly in recirculating setups.

Usage Guidelines

This section covers practical guidance for setting up and maintaining the AutoPot 3.3′ x 3.3′ Square Garden Tray in a growing environment. Because this is a passive tray with no moving parts, usage guidance centers on placement, loading, drainage management, and cleaning.

• Check exact dimensions before placing. The manufacturer notes that this tray is “slightly larger” than its 3.3′ nominal designation – the actual external measurement is 39.5″ on each side. Measure the intended floor or bench space against 39.5″ before purchasing or positioning the tray.
• Position pots on the internal ridges. The ridges on the tray floor are functional: they create a slight elevation between the pot base and any pooled liquid. This keeps the base of the pot out of standing solution, which is particularly relevant in AutoPot systems where the AQUAvalve cycles the tray between filled and empty states.
• Monitor solution levels. With a 26-gallon capacity, this tray can hold a large volume of runoff before it becomes visually apparent at the tray rim. In systems where runoff is recirculated or drained on a schedule, check that drainage intervals are appropriate for the volume of solution being applied to the pots sitting in the tray.
• Drain and clean regularly. In non-recirculating setups, drain accumulated runoff regularly to prevent salt buildup on the tray floor and the base of pots. Flush the tray with clean water between crop cycles and inspect the ridges for algae or residue accumulation.
• Commercial spillage applications. When used as a spillage containment tray for chemical storage, check local regulations for secondary containment volume requirements. The 26-gallon capacity should be compared against the volume of containers being stored above the tray to confirm adequate containment.

How to Set Up the AutoPot 3.3′ x 3.3′ Square Garden Tray

1. Verify clearance. Measure the installation area. The tray external footprint is 39.5″ x 39.5″. Allow additional clearance around the tray for access and drainage management.
2. Level the surface. Place the tray on a flat, level surface. Uneven placement will cause solution to pool at one end of the tray, which can result in unequal exposure of pot bases to standing liquid and inaccurate drainage timing in gravity-fed systems.
3. Inspect before use. Check the tray for cracks or deformations, particularly along the base corners, before loading pots or liquid. Polypropylene is durable but can stress-crack if dropped or overloaded on an unsupported span.
4. Place pots on the ridges. Set plant pots directly onto the internal ridge pattern. The ridges are shallow and will not significantly elevate the pots, but they provide enough separation to allow liquid to flow beneath the pot base toward the tray center and corners.
5. Connect to system plumbing if applicable. If the tray is integrated into an AutoPot gravity-fed system, connect the AQUAvalve or supply line to the designated inlet point per the AutoPot system instructions. The tray itself has no built-in fittings; connection points are determined by the AutoPot system module being used.
6. Establish a drainage routine. Decide whether runoff will be drained manually, collected via a submersible pump, or managed through a recirculation loop. With 26 gallons of capacity, unscheduled accumulation can go unnoticed for an extended period in high-output systems.
7. Clean between crop cycles. After harvest, remove all pots and media. Rinse the tray thoroughly with clean water. For heavy mineral deposits, a dilute citric acid solution is effective on polypropylene without degrading the material.

Sources & Further Reading