Optic Foliar FAQ's
With lights off or at low intensity. Droplets sitting on a leaf under full-strength lighting can cause damage, and the plant absorbs more when stomata are open rather than closed against heat. Early in the dark period or just before lights on are the usual windows. Avoid spraying dense flowers late in the cycle, where trapped moisture invites mould.
Transport is the carrier product and the one most growers start with; Switch, Rev and Overgrow each target a different point in the cycle. They are designed as a range rather than as competing options, so the question is usually which stage you are at rather than which product is best. Sizes run 250mL to 4L depending on the item.
No — foliar sprays go on the leaf, not in the reservoir. Adding them to a nutrient tank wastes the product and can cause unpredictable reactions with concentrated nutrients. Mix foliar products in a clean dedicated sprayer, and rinse that sprayer between different products so residue does not carry over.
Cover the undersides of leaves as well as the tops. Stomata — the pores through which leaves take things in — are concentrated on the underside, and that is also where most pests shelter. A spray that only wets the upper surface is doing perhaps half the job it could. Work from below where the canopy allows.
The range runs 250mL, 500mL, 1L and 4L depending on the product, with Switch available in the 4L format for commercial application. For a home grower a 250mL bottle of a concentrated foliar goes a long way, since foliar spraying covers leaf surface rather than filling a reservoir.