Super Sprouter Double Thick Tray 10 x 20 – No Hole

The Super Sprouter Double Thick Tray 10 x 20 — No Hole is a heavy-duty propagation flat built to twice the thickness of standard 10 x 20 trays so it lasts season after season. The solid bottom holds excess water to keep clones, seedlings, and rock wool plugs moist, while raised channels molded into the tray floor allow air to circulate beneath insert trays, pots, and plug sheets. It is the workhorse no-hole flat for any propagation bench, dome setup, or bottom-watering routine where moisture retention matters more than drainage.

Super Sprouter Double Thick Tray 10 x 20 No-Hole Specifications

The specifications below come from the canonical supplier listing at Cultivate Supply, confirmed third-party retailer data at Hydrobuilder and Monster Gardens, and Super Sprouter / Hawthorne Gardening Company brand catalog language. All measurements are for the single tray, no-hole variant in the SKU HGC726297.

Specification	Value
Brand	Super Sprouter (Hawthorne Gardening Company)
Supplier SKU	HGC726297
UPC (case of 50)	10849969000761
Dimensions	10 in x 20 in (standard propagation flat footprint)
Thickness	Double the thickness of standard Super Sprouter 10 x 20 trays
Drainage	No holes — solid bottom retains water for moisture-holding propagation
Base design	Raised channels molded into the tray floor for air circulation under inserts
Material	Injection-molded plastic
Weight (single tray)	0.56 lb
Pack-of-50 weight	28.0 lb
Sold as	Single tray (also available in case packs of 50)
Product line	Super Sprouter propagation trays (standard, double thick, triple thick, quad thick variants)
Companion variant	Super Sprouter Double Thick Tray 10 x 20 — With Hole (drains excess water rather than retaining)
Reusability	Designed for multi-season reuse — brand language: “last season after season”

Why Choose the Super Sprouter Double Thick No-Hole Tray

The points below are grounded in the official Super Sprouter brand catalog language, the canonical supplier description, and confirmed third-party retailer specifications. Each addresses a specific reason a propagator might choose the double thick no-hole tray over alternatives.

• Double the thickness of standard 10 x 20 trays for true multi-season durability. Standard single-thickness propagation trays are thin enough to flex, crack, and split when lifted while full of plugs or wet media. The Super Sprouter Double Thick tray is molded to twice that thickness, which is the brand’s direct response to growers who go through several flats per crop cycle. The brand catalog language is explicit: “double the thickness of our standard trays ensuring it will last season after season.” For commercial propagators running back-to-back rotations, this is the difference between buying new flats every cycle and reusing the same flats for years. Hydrobuilder lists the double thick line as “industry standard in strength and durability” in its catalog — positioning the tray as the entry-level durability step up from standard, with the triple and quad thick variants available for higher-reuse applications.
• Solid no-hole bottom retains water and keeps starts moist. Unlike the with-hole variant in the same line, this tray has a fully sealed bottom. That is a deliberate design choice for two specific propagation workflows. First, bottom watering: pour nutrient solution or plain water directly into the tray, set rockwool cubes, plug sheets, or insert trays on top, and let capillary action wick moisture into the rooting media from below. The tray holds the water in place until plants take it up, eliminating the runoff cleanup that comes with drainage trays. Second, moisture retention under humidity domes: cuttings and seedlings need consistent high humidity to root and germinate, and a no-hole tray keeps the substrate moist between waterings without forcing the propagator to mist constantly. The brand language captures the choice precisely: “available without holes to catch excess water and help to keep starts or plants moist.”
• Raised drainage channels under the substrate prevent stagnation. The tray floor is not flat. Super Sprouter molds raised channels into the base so that when an insert tray, pot, or plug sheet sits inside the no-hole tray, the substrate does not sit directly on a pool of water. Air circulates beneath the inserts through the channels, which limits stagnation, anaerobic conditions, and the damping-off pathogens that thrive when roots sit submerged. This design lets the tray hold a reservoir of water for capillary uptake while keeping the plug or insert base elevated above the pooled liquid. It is the same engineering principle behind capillary mats, executed in the tray geometry itself.
• Standard 10 x 20 footprint fits every propagation accessory in the category. The 10 in x 20 in outer dimension is the de facto standard for North American propagation hardware. Every humidity dome, insert tray, plug sheet, heat mat, dome vent, and propagation rack on the market is built to that footprint. A double thick no-hole tray drops into any existing propagation setup without modification. Replace a worn-out standard tray with a double thick and every dome, insert, and accessory still fits. For growers building a new propagation bench from scratch, the standard footprint guarantees compatibility with future accessories and inserts as the operation scales.
• Made by a dedicated propagation brand within Hawthorne Gardening. Super Sprouter is the propagation-specific brand inside the Hawthorne Gardening Company catalog. The brand focuses on trays, domes, T5 propagation lighting, heat mats, and seedling nutrients rather than offering trays as a peripheral SKU. That focus shows in the molded raised channels, the multi-thickness durability ladder (standard, double, triple, quad), and the paired holed and unholed variants for different watering workflows.

Best Uses for the Super Sprouter Double Thick No-Hole Tray

The use cases below are derived from the official Super Sprouter brand description, confirmed retailer data, and standard propagation practice for 10 x 20 trays. Each reflects a workflow where the no-hole tray’s moisture retention and raised-channel base provide a functional advantage over drainage trays or generic flats.

• Bottom-watering rockwool, oasis, and starter plugs. Bottom watering is the standard practice for rooting clones and germinating seeds in rockwool cubes, oasis cubes, peat plugs, and similar moisture-sensitive media. Pour the watering solution directly into the no-hole tray, set the plug sheet or cube tray on top of the raised channels, and let the substrate wick moisture from below. The plugs absorb only as much as they need, the tray holds the rest until the next wicking cycle, and there is no top-down water displacement that could disturb seeds or unrooted cuttings. The raised channels keep the plug bases elevated above the pooled solution, so the media never sits fully submerged.
• Catchment under humidity domes for clone rooting. Rooting cuttings under a humidity dome requires the substrate to stay moist without saturated runoff puddling on the bench surface. Drop a propagation insert with rooting clones into the no-hole tray, cap with a 10 x 20 humidity dome, and the tray holds any condensation that drips from the dome interior plus any excess moisture from misting cycles. The sealed bottom prevents bench-surface water damage, and the raised channels keep the insert base from sitting in pooled water that could promote stem rot at the cutting base.
• Seed germination flats with seedling mix. Filled with a light seedling mix or sown directly with seeds, the no-hole tray functions as a self-contained germination flat. Water from below by misting the surface lightly and adding small amounts to the tray base; the seedling mix wicks moisture upward through capillary action while the no-hole bottom prevents the bench from getting wet. This is especially useful for slow-germinating seeds that need the substrate to stay consistently moist over a 1–3 week germination window without daily misting attention.
• Drip catchment under potted starts and small containers. Set a row of 4-inch nursery pots, 1-gallon nursery containers, or fabric pots into the tray and use it as a catchment basin for runoff and overwatering. The 10 x 20 footprint holds approximately a dozen 4-inch pots or four 1-gallon containers. Because there are no drainage holes, the tray retains everything that runs out the bottom of the pots, which is useful for indoor growing surfaces where bench-surface water damage is a concern. Empty the tray periodically by tipping it carefully or wicking the standing water with a sponge.
• Microgreen production flats and harvest catchment. Microgreen production typically uses 10 x 20 flats stacked in a multi-tier rack. The no-hole double thick tray works as the bottom catchment layer under perforated microgreen production flats — the perforated flat sits on top of the raised channels with seedling mix, and the bottom tray catches drainage during watering. For multi-week production cycles, the heavier tray construction survives repeated handling between the rack, sink, and harvest station without splitting. Pair the tray with the right growing media to match your crop — for a moisture-retentive germination mix that suits seedling and microgreen production, see the Premier Pro-Mix HP with mycorrhizae in the larger 3.8 cu ft bale size for commercial volume.
• Pairing with the “with hole” sibling for two-tray nested watering. A common professional propagation setup uses two trays nested together: a no-hole tray on the bottom holding a reservoir of water, and a with-hole tray nested inside holding the substrate and inserts. The bottom tray catches and stores water, the top tray drains excess into the bottom, and the substrate stays moist via wicking without ever sitting in standing water. This nested-tray approach is one of the simplest, lowest-cost capillary watering setups available, and the Super Sprouter line offers both variants in matching dimensions specifically to support this workflow.

Super Sprouter Double Thick No-Hole vs Standard and Quad Thick Trays

The Super Sprouter 10 x 20 tray line comes in four thickness tiers: standard, double thick, triple thick, and quad thick. Each tier targets a different reuse frequency and durability requirement. Understanding where the double thick sits in that ladder helps you choose the right tray for your operation.

Key trade-offs:

• Double thick vs standard single-thickness trays. Standard Super Sprouter trays (and generic 10 x 20 propagation flats sold in bulk case quantities by brands like Bootstrap Farmer and other generic suppliers) are thin enough to flex under the weight of a fully wet plug sheet and tend to crack at corners or split along stress lines within a few crop cycles. The double thick tray is molded at twice that thickness, eliminating the flex and extending usable life from one-to-three cycles to multiple seasons. For low-volume hobby propagators running one or two flats per year, the standard tray cost savings make sense. For any operator running flats month after month or moving them repeatedly between bench, sink, and rack, the double thick is the more economical choice over the tray’s service life.
• Double thick vs quad thick (Super Sprouter Quad Thick Tray and Insert). The quad thick variant in the same brand line is four times the thickness of standard trays and is positioned as the maximum-durability option for commercial propagation where flats are cycled aggressively across many crop rotations. Quad thick trays are heavier per unit, more expensive, and harder to flex even when fully loaded. For commercial growers running propagation cycles continuously year-round with heavy bench handling, the quad thick pays back its price premium in extended service life. For the typical small commercial or serious hobby propagator running seasonal cycles, the double thick offers most of the durability benefit at a more accessible price point.
• No-hole vs with-hole variant in the same double thick tier. The two variants share identical 10 x 20 dimensions, raised channel base design, and double thickness construction — they differ only in whether the bottom is solid or perforated. The no-hole variant retains water for bottom watering, humidity dome catchment, and moisture-loving propagation workflows. The with-hole variant drains excess water and is used for top-watering applications where saturation must be avoided. Many propagators keep both variants on hand and select between them based on the specific media, plant stage, and watering schedule of each crop.
• Weight and handling differences across the line. At 0.56 lb per tray, the double thick is light enough to lift one-handed even when fully loaded with wet substrate and inserts. The quad thick is heavier and more rigid — better for stationary bench applications. For workflows with frequent tray relocation, the double thick weight is the practical sweet spot.
• Price and pack quantity economics. Sold individually at retail and in case packs of 50 (28.0 lb total) for bulk-buyer pricing. Commercial propagators typically buy the case pack; hobby propagators or growers testing a new workflow can buy single trays.

Compatibility & Operating Range

The compatibility information below is drawn from the canonical Super Sprouter product description, confirmed retailer listings, and standard propagation practice for 10 x 20 propagation hardware. All clearances and dimensions are specific to the 10 in x 20 in footprint.

• Standard 10 x 20 humidity domes. Every major 10 x 20 humidity dome on the market — including the Super Sprouter tall and short dome variants, Mondi Mini Greenhouse domes, and generic propagation domes — sits on the rim of the tray with the dome edges aligning to the tray rim. Verify dome height clearance against your shelf or rack tier; tall domes (7 in or higher) need correspondingly tall tier spacing on multi-tier propagation racks.
• 10 x 20 insert trays, plug sheets, and cube sheets. The tray accepts every 10 x 20 propagation insert in the category. Common inserts that drop into the tray include 50-cell, 72-cell, and 128-cell plug sheets; rockwool cube sheets in 1.5 in or 2 in cube sizes; oasis root cube sheets; and peat or coir starter plug sheets. The raised channels in the tray floor lift the insert base above any pooled water, so the inserts function correctly without sitting in standing solution. For a small-cell insert solution that pairs with the no-hole tray and includes its own dome, see the 50-cell incubator insert tray with outer tray and dome bundle.
• Heat mats and seedling heat strips. Standard 10 x 20 seedling heat mats sit directly under the tray and warm the substrate from below. The tray’s no-hole bottom prevents water from dripping onto the heat mat surface during watering or condensation cycles, which protects the heat mat’s electrical components and extends its service life. Verify the heat mat’s temperature controller setpoint is appropriate for the seeds or cuttings (typically 70–85°F / 21–29°C for most propagation work).
• Propagation racks and bench shelving. The 10 in x 20 in footprint is the dimensional standard for every propagation rack on the market, from compact 2-tier home propagation stands to commercial 8-tier propagation carts. The tray fits on standard wire shelving with 12-inch or deeper shelves; for 10-inch wire shelving, the tray hangs over slightly on one edge but remains stable. The light 0.56 lb empty weight keeps total per-tier load low, leaving headroom for filled-tray weight (substrate, plants, inserts, and retained water).
• Operating temperature range. Injection-molded propagation tray plastic is rated for continuous use across the temperature range found in typical indoor and greenhouse propagation environments (55–95°F / 13–35°C ambient, with substrate temperatures up to 85°F / 29°C). For sustained outdoor or hot greenhouse use with direct UV exposure, the tray surface can become brittle over months of continuous exposure; for those environments, position the tray under canopy shade or inside a structure to limit UV.
• Cleaning agents and sanitizers. The tray is compatible with diluted bleach (1:10 with water), 3% hydrogen peroxide, isopropyl alcohol, and standard quaternary ammonium sanitizers at manufacturer-recommended dilutions. Avoid prolonged contact with concentrated acetone, MEK, or other aggressive solvents that can craze or soften the plastic. For mineral salt buildup from repeated nutrient-solution use, white vinegar diluted 1:4 with water and a 15–30 minute soak removes most deposits without damaging the tray surface.
• Pairing with other propagation hardware. Match the no-hole tray with a humidity dome, a plug or insert sheet of your choice, a heat mat for warmth-loving seeds, and a propagation-spectrum T5 fluorescent or LED for seedling light. For containment under fabric pots or larger nursery containers in a growing area, the larger-footprint Smart Pot 3 gallon fits well alongside the tray on a propagation-to-veg transition bench.

Usage Guidelines for the Double Thick No-Hole Tray

The guidelines below cover practical operation of the Super Sprouter Double Thick No-Hole Tray across its primary propagation use cases. Information is drawn from the canonical Super Sprouter description, confirmed retailer specifications, and standard propagation practice for no-hole 10 x 20 trays.

Initial cleaning before first use. Wipe the tray interior and exterior with a damp cloth to remove any plastic residue or handling dust from shipping. For propagation applications that are especially sensitive to contamination (commercial clone production, tissue culture transfer, valuable seed stock), follow the wipe-down with a sanitizing rinse: 3% hydrogen peroxide applied to all surfaces, allowed to sit for 10 minutes, then rinsed with clean water and air-dried. The tray ships clean from the manufacturer but a sanitizing pass before first use reduces the risk of carrying any introduced contamination into a sterile substrate.

Bottom-watering rockwool and plug sheets. Fill the tray with 0.5–1 cup of nutrient solution or plain water (depending on the substrate’s saturation state). Set the plug sheet or rockwool cube tray on top of the raised channels and let the substrate wick moisture for 10–15 minutes. Lift the plug sheet briefly to verify the base feels moist but not dripping; if still dry, add water in small increments. After the plugs are saturated, drain any remaining water from the tray by tipping or wicking with a sponge to avoid prolonged submersion. Repeat the bottom-water cycle every 2–4 days depending on substrate type, ambient humidity, and plant stage.

Humidity dome catchment for clones. Place rooted or unrooted cuttings in a 10 x 20 insert tray and set it inside the no-hole tray. Mist the cuttings with plain water and cap with a 10 x 20 humidity dome. The dome traps moisture and creates a 90–100% relative humidity environment. Any condensation that drips from the dome interior and any runoff from misting collects in the bottom tray. Open the dome vents for 5–10 minutes per day to exchange air and prevent fungal buildup; once cuttings show new growth, open vents progressively over 7–14 days to acclimate them to lower humidity before removing the dome.

Seed germination flats. Fill the tray with 0.5–1 inch of seedling mix or sow seeds directly on a thin layer of pre-moistened seedling mix. Mist the surface to settle the mix without displacing seeds, then cover with a humidity dome to retain moisture. For seeds that need bottom heat, set a seedling heat mat under the tray and use a temperature controller to maintain substrate temperature in the 70–85°F range. The no-hole tray retains moisture for the full germination window without requiring daily misting attention.

Drip catchment under potted plants. Set 4-inch nursery pots, fabric pots, or 1-gallon nursery containers on top of the raised channels. The tray catches drainage water from watering or feeding cycles, holding it until you empty it. For propagation-to-veg transitions where plants graduate from plug to pot, this configuration keeps the bench clean while plants establish in their new containers. Monitor the catchment level — if water rises above the raised channel height, the pot bases sit in pooled water and root health can suffer; empty the tray before that occurs.

Inspection for damage between cycles. Despite the double thick construction, inspect the tray between crop cycles for hairline cracks at the corners or edges where dropped or bent trays can fail. A cracked no-hole tray will slowly leak through the floor and behave like a holed tray, which defeats the moisture-retention purpose. Retire any cracked trays from no-hole service (they may still work for top-watered drainage applications) and replace with a fresh tray for moisture-retention cycles.

Cleaning between crop cycles. Remove all substrate, inserts, and root debris from the tray. Rinse with plain water, then apply 1:10 diluted bleach or a propagation-rated sanitizer to all surfaces. Let the sanitizer sit for the manufacturer-recommended contact time (typically 10 minutes), then rinse thoroughly with clean water and air-dry before the next cycle. For mineral deposits from repeated nutrient solution use, soak the tray in 1:4 diluted white vinegar for 15–30 minutes and scrub the raised channels with a soft-bristle brush before rinsing.

How to Set Up a Bottom-Watering Propagation Station with the No-Hole Tray

The steps below describe setting up a complete bottom-watering propagation station using the Super Sprouter Double Thick No-Hole Tray as the moisture reservoir. The same setup principle applies whether you are rooting clones, germinating seeds, or producing microgreens.

1. Inspect and sanitize the tray. Wipe the tray interior with a damp cloth, then apply 3% hydrogen peroxide or a 1:10 diluted bleach solution to all surfaces. Let sit for 10 minutes, rinse with clean water, and air-dry on a clean surface. Verify there are no hairline cracks at the corners or edges before using.
2. Position the tray on a level surface. Place the tray on a propagation bench, wire shelving, or workbench surface that is flat and level. Use a bubble level to check both axes — a tilted tray will pool water on one side, leaving the high-side substrate dry. For wire shelving, place a rigid liner (acrylic sheet or plywood) under the tray to prevent uneven support from the wire crossbars.
3. Add a heat mat if needed. For seeds or cuttings that need bottom heat, set a 10 x 20 seedling heat mat under the tray and plug it into a temperature controller set for 70–85°F substrate target. The no-hole tray bottom protects the heat mat from any water exposure that would damage its electrical components.
4. Pour the initial water charge into the tray. Add 0.5–1 cup of plain water or properly mixed nutrient solution into the tray base. The raised channels keep the water in the spaces between the channels rather than spreading it as a flat surface puddle.
5. Place the plug sheet or insert on the raised channels. Drop the rockwool cube sheet, plug sheet, or insert tray onto the raised channels. The insert base should sit on top of the channels with the substrate beginning to wick water from below within a few minutes.
6. Plant the cuttings or seeds. Insert clones into the rockwool or plug holes, or sow seeds directly into the moistened substrate. Mist the tops lightly to settle the substrate around the cuttings or seeds without displacing them.
7. Cap with a humidity dome and adjust vents. Place a 10 x 20 humidity dome over the insert and tray assembly. Adjust the dome vents to fully closed for the first 24–48 hours of clone rooting or seed germination to maintain high humidity, then open vents progressively as the plants establish.
8. Add propagation light above the dome. Position a propagation-spectrum T5 fluorescent or LED light 6–12 inches above the dome surface. Run lighting on a 16–18 hour photoperiod for active vegetative propagation; reduce to 12 hours for some heat-sensitive seed germination.
9. Monitor and refill water as needed. Check the tray every 1–2 days. When the standing water is fully absorbed and the substrate begins to feel less moist, add another 0.5–1 cup of water to refill the reservoir. Avoid overfilling — water should never rise above the raised channel height, or the substrate will sit in pooled water and stagnate.
10. Transition out of the dome. When cuttings show new top growth or seedlings develop their first true leaves, open dome vents over 7–14 days to acclimate plants to lower humidity. Once they are stable without the dome, transfer the plug sheets to a vegetative-stage bench and prepare the no-hole tray for the next propagation cycle with a thorough cleaning and sanitization pass.

Sources & Further Reading