Seed Germination Trays

Seed Germination Trays

Choose cell count, width and depth

Compare plug cavity measurements with your transplant plan and available shelf height.

Start with the cell opening

Measure the cavity width at its top and check whether the sides taper. Two flats with the same total cell count can differ in depth and usable space per plug.

Choose batch density deliberately

A dense flat puts more plugs within one footprint. Wider modules give a batch more space per plant and can be easier to move separately when individual starts grow at different rates.

Check the whole tray height

The depth of a cavity and the overall height of a flat can differ. Check both dimensions for stacking and cover clearance, then read the supplier’s crop and transplant guidance for your needs.

Source documentation

Guide questions

Does a deeper flat always hold more plants?

Depth and cell count are separate. Deeper and wider cavities can come with fewer cells per flat.

Why compare the opening and the depth together?

Both affect the space available for a plug. The opening alone gives no measure of its vertical room.

When do removable modules help?

They let you move one group independently when batches germinate or become ready at different times.

Which accessory suits the job?

  1. Bootstrap Farmer lists the same 2.25-inch depth for these inserts. Choose the 128-cell grid for a one-inch opening or the 200-cell grid for more, narrower plugs.

    Bootstrap Farmer 128-cell plug flats, pack of 10 ↗Bootstrap Farmer 200-cell plug flats, pack of 10 ↗

  2. The 18-cell RooTrimmer gives a three-inch square opening. The 40-cell flat has a smaller opening and a greater listed depth. Compare the available width, height and batch count.

    RooTrimmer 18-cell wide deep plug trays, pack of 10 ↗RooTrimmer 40-cell extra-deep plug trays, pack of 10 ↗

Accessories in this guide

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