If you operate a commercial vegetable nursery, produce seedlings for open fields or greenhouses, have an urban garden project with your own production, propagate ornamental plants from cuttings, or work in serial forestry production, the GARDESE horticultural tray with UV treatment and conical concave cell geometry is the calibrated tool for these scenarios. This guide explains how to choose between the four configurations (72, 128, 200, and 288 cells) according to the crop and cycle, how to prepare the substrate and sow, how to water for germination without damping-off, and how to extract the seedling with an intact root ball for successful transplanting.
The horticultural tray is the format with individual cells. For hydroponic green fodder, microgreens, massive germination with continuous root mat, or block harvesting, the correct format is NOT the horticultural tray but the flat hydroponic tray without cells. Confusing the formats will result in losing the appropriate geometry: individual cells do not allow for the continuous mat of hydroponic green fodder, and the flat tray does not isolate each seedling for transplanting with an intact root ball.
Product Specifications
The horticultural tray is offered in four configurations differentiated by the number of cells, presented in boxes of 140 to 160 units depending on the format. The following table provides the full technical specifications for all four variants:
| Specification | 72 cells | 128 cells | 200 cells | 288 cells |
|---|---|---|---|---|
| SKU | 589231 | 623230 | 730212 | 123423 |
| Material | Plastic resin with UV | Plastic resin with UV | Plastic resin with UV | Plastic resin with UV |
| Geometry | Large conical cells | Medium conical cells | Small conical cells | Minimum conical cells |
| Volume per cell (approx.) | ~50-60 ml | ~25-35 ml | ~12-18 ml | ~8-12 ml |
| Box | 160 trays | 160 trays | 140 trays | 160 trays |
| Seedlings per box | 11,520 | 20,480 | 28,000 | 46,080 |
| Maximum time in tray | 8-12 weeks | 5-7 weeks | 3-4 weeks | 2-3 weeks |
| Typical crops | Woody cuttings, ornamentals | Tomato, bell pepper, eggplant, broccoli, cabbage | Lettuce, cilantro, parsley, leafy greens | Onion, mini lettuces, microgreens in cells |
| Drainage | Bottom hole per cell | Bottom hole per cell | Bottom hole per cell | Bottom hole per cell |
| UV Treatment | Yes | Yes | Yes | Yes |
More cells = more seedlings per tray, but less root volume per plant and therefore earlier and mandatory transplanting. Fewer cells = more volume for root development, more tolerance time in the tray before transplanting. The correct choice is the minimum number of cells that provides sufficient space for the crop during the planned time in the tray —too many cells (over-density) leads to leggy seedlings, coiled roots, and transplant shock; too few wastes nursery space—.
The flat hydroponic tray without cells is the choice when the goal is the production of a continuous root mat (hydroponic green fodder, microgreens, block harvesting) instead of individual seedlings for transplanting.
Step-by-step guide to use
The following procedure covers the complete cycle of the horticultural tray: format selection, substrate preparation, sowing, watering, germination, and extraction for transplanting. The instructions apply to all four variants with specific notes depending on cell size.
Selecting the number of cells according to the crop
Choose the format according to the crop and the anticipated time in the tray before transplanting. For woody and semi-woody cuttings of ornamental plants, miniature fruit trees, and forest plants with prolonged rooting times (8-12 weeks), use 72 cells. For medium-sized vegetables with a seedling cycle of 5-7 weeks (tomato, bell pepper, eggplant, broccoli, cabbage, cauliflower), use 128 cells —the standard format for commercial horticultural nurseries—. For leafy vegetables with a fast cycle of 3-4 weeks (lettuce, cilantro, parsley, dill, aromatic herbs), use 200 cells. For onion, garlic, miniature lettuces, and mass production with transplanting in 2-3 weeks, use 288 cells. If you are unsure about a new crop, step down one density level from the rule above —too many cells penalizes the result more than too few—.
Substrate preparation and filling
Use a specific germination substrate: a mixture of peat or coco coir with perlite and vermiculite in a typical ratio of 60-70% peat/coco coir + 15-20% perlite + 15-20% vermiculite. Moisten the substrate to field capacity —when squeezed between fingers, it forms a "clump" that crumbles easily, without dripping water—. Distribute the substrate over the tray, gently press with the palm of your hand so that each cell is filled to the rim without excessive compaction. Remove any excess with a ruler by sweeping across the surface. Excessive substrate compaction blocks drainage and hinders germination; loose substrate sinks with watering, leaving half-empty cells.
Sowing and covering
Sow 1-2 seeds per cell (1 seed with a high and certified germination rate, 2 seeds with questionable material, thinning out the weaker one later). The sowing depth is 2-3 times the seed diameter —small seeds (lettuce, herbs) almost superficial; medium seeds (tomato, broccoli) at 0.5-1 cm; large seeds (beans, sweet corn) at 1-2 cm—. For very small or light-sensitive seeds (lettuce, celery), do not cover with additional substrate, just press lightly so they touch the moist medium. For the rest, sprinkle a thin layer of vermiculite on top as a cover, then water with a fine-rose watering can or micro-sprinkler to avoid displacing the seeds.
The trick for seedlings to come out with an intact and clean root ball at transplant time is to thoroughly water the ENTIRE tray 30-60 minutes before extraction. The saturated substrate adheres the fine roots into a coherent mass that comes out whole when gently pressed from below with a finger (through the drainage hole) or pulled by the base of the stem. Without this pre-watering, the root ball crumbles, fine roots break, and the seedling suffers transplant shock that can delay growth by 1-2 weeks. This practice, standard in professional nurseries, distinguishes a seedling that thrives in the field from one that wilts. Additionally, avoid transplanting in the Caribbean midday —choose early morning or sunset— so that thermal shock does not add to extraction shock.
Watering, germination, and in-tray management
Keep the tray in germination conditions with constant moisture but NEVER waterlogged—substrate that is always saturated promotes damping-off, a collar rot fungus that fells newly emerged seedlings within hours. Water with a fine-nozzle watering can or micro-sprinkler 1-2 times a day in Caribbean climates, adjusting according to evaporation. For germination, keep the trays at 22-28 °C covered with clear plastic or a dome until emergence, uncovering as soon as the first shoots appear to prevent excessive elongation due to high humidity and low light. After emergence, move the trays to an area with direct light or a greenhouse with partial shade. Apply gentle fertigation with a seedling formula starting from the second pair of true leaves.