Quick verdict
Five mesh trays and five solid trays, 14 by 12 by 3 inches, in BPA-free plastic, that nest so soil blocks or microgreens sit on the mesh and the solid tray below holds water for bottom watering and catches drainage. Soil blocks need bottom watering and air at their base; a mesh tray over a solid one gives both and lets a whole tray of blocks lift and move as one. Three inches of depth suits 2 inch blocks with headroom. Heavy enough to carry wet.
Strengths
- Mesh over solid gives bottom watering and air at the block base
- Lift and move a full tray of blocks without disturbing them
- Five of each tray for a season of successions
- BPA-free plastic, reusable
- Three inch depth suits 2 inch blocks and microgreens
Weaknesses
- Fourteen by 12 inches is not the 1020 standard; check shelf fit
- Solid trays hold limited water; refill often in warm rooms
- Mesh openings let fine mix fall through on the first watering
The overall YardToolLab Score is out of 100. Section scores are out of 10.
The Tray a Soil Block Needs
Soil blocks have no pot. They need water from below and air at their base so roots prune at the edge, and they need to be moved without being touched. A mesh tray in a solid tray does all of it. RooTrimmer’s set is five mesh trays and five solid trays, 14 by 12 by 3 inches, in BPA-free plastic, for blocks and for microgreens.
This review is based on the maker’s specifications and on how two-part trays perform for soil blocking and microgreens generally. We have not used these trays ourselves.
Bottom Watering
Pour water into the solid tray and it wicks up through the mesh into the blocks. The block bases stay in air rather than a puddle, so roots reach the edge and stop, and the top of the block stays dry, which keeps damping off away. For microgreens, the same arrangement waters the mat from below and keeps the leaves dry.
Moving Blocks
Lift the mesh tray and 30 or 40 blocks move together to the greenhouse, the cold frame or the hardening-off bench without a hand touching them. Drain a tray by lifting the mesh for a minute. That is the convenience a single tray cannot give.
Size
Fourteen by 12 inches is close to a 1020 flat and not the same; check it fits the shelf or the light stand. Three inches of depth takes 2 inch blocks with room for seedlings before they move on, and suits a dense microgreen crop.
Care
Wash with mild bleach solution between crops and store nested. The plastic is sturdy enough to carry a wet tray by the rim.
Who Should Buy It
- Soil blockers who need to water and move blocks cleanly.
- Microgreen growers wanting bottom watering.
- Seed starters replacing flimsy single trays.
Common Owner Complaints
Not quite 1020 size and limited water in the solid tray. Measure the shelf; top up daily in warm rooms.
Technique Tips
Put a thin layer of damp mix in the mesh tray before setting blocks so the first bottom watering does not wash fines through. Fill the solid tray to a depth of half an inch and let it be absorbed before adding more; standing water at the block base defeats the air pruning. Label each tray on the rim with tape, since a bench of identical trays of identical blocks is impossible to tell apart.
Alternatives to Consider
Bootstrap Farmer 1020 mesh and solid trays in the standard size. The RooTrimmer ebb and flow shelf for automated watering. A capillary mat in a single tray for a cheaper version.
Verdict
For soil blocks and microgreens, a mesh tray in a solid tray is the right setup and this five-pack of each equips a season. Check the shelf fit, water from below and lift the mesh to move.
Full specifications
RooTrimmer 5-Pack 14 x 12 x 3 Inch Soil Blocking Trays with 5 Mesh and 5 Solid Trays FAQs
Set the mesh tray in the solid tray, place blocks or sow microgreens on the mesh, and pour water into the solid tray. Water wicks up and air reaches the base; lift the mesh tray out to move or drain.
Roughly 30 to 40 per tray depending on spacing. Leave a finger between blocks so roots air-prune.
They are 14 by 12, a little wider and shorter than a 1020 flat. Measure the shelf.
No. Two inch blocks sit on the mesh; a little loose mix falls through on the first watering and then the block holds.
