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Zone · Grow lights · Grow light bulb

Zone Grow light bulb — Full-spectrum LED grow light bulb with an E26 base

Zone Grow light bulb — Full-spectrum LED grow light bulb with an E26 base. Shown on the grow colour field.

Zone Grow light bulb, shown in a typical installation (illustration)
In a typical installation · illustration, product at its own colour temperature
Who it's for / where it goes

The grow bulb is for indoor gardeners using an appropriate E26 lamp holder above plants. Its tall body and published plant-light output make fixture fit and the plants’ position separate decisions: a bulb can fit the socket while still sitting too close to a shade or leaves.

Check before you buy
  • Size and fit. Published size: 3.54 x 3.54 x 8.66 in. Bigger than a household bulb: about 3.5 in across and 8.7 in tall. An ordinary bulb is about 2.4 in across and 4.3 in tall, so check it fits your fixture, shade or cage. Measure the fixture opening, available height and the space above the plants as they grow. Compare both bulb width and height with the published dimensions. The E26 base does not establish enclosed-fixture permission, and the plant-light figure does not tell you how many pots fit beneath it.
  • Brightness. Grow spectrum; household-bulb equivalents do not measure plant coverage.
  • Power and installation. E26 socket (screw-in). Check the socket, fixture limits and clearance before screwing it in. Electrical rating: 40 W.
  • Location. Damp locations.
  • Controls. Dimming: No, not for use with dimmers.
Specifications, as printed
Size3.54 x 3.54 x 8.66 in
Colour temperatureFull spectrum · red and blue
Watts40 W
PowerE26 socket (screw-in)
DimmableNo, not for use with dimmers
LocationDamp locations
Warranty2-year limited
ListingETL listed

Unpublished: delivered lumens. Ask about Z-GR-CB40.

Questions buyers ask

What’s the difference between PPF and PPFD?

The Z-GR-CB40 record publishes a PPF figure, which describes total plant-light output rather than an area on your shelf. PPFD measures light arriving at an area. Coverage depends on distance and distribution as well as the plants. Ask for a suitable coverage measurement and placement guidance instead of dividing that figure by the number of pots. Full guide: Grow light colour.

Does an E26 grow bulb fit any E26 lamp?

Z-GR-CB40 is a tall grow bulb, so a matching socket is only one part of the fit check. Compare the full height and width with the shade and with the space between the fixture and future foliage. Use its actual electrical wattage for the holder’s limit. The PPF value does not relax those fixture requirements, and no enclosed-fixture permission is supplied on this page. Full guide: Grow light bulbs, strips or fixtures.

Can I run a grow light longer to make up for a weak one?

This bulb’s plant-light output figure does not tell you whether a particular leaf is receiving enough light at your chosen distance. Extending the schedule cannot be assumed to solve poor placement, shade from other plants or an unsuitable footprint. Share the plant types and arrangement when asking for coverage guidance. Z-GR-CB40 is also non-dimmable, so do not plan a wall dimmer as the way to adjust its output for different shelf positions. Full guide: Grow light colour.

Compare with

All 12 grow lights →
Grow light bulb: same-type options first, then other grow lights.
ProductLumensPower / wattsPublished sizeLocation
A19 grow light bulbZ-GR-A19-3SNot published — ask usE26 socket (screw-in)
9 W		Not published — ask usDamp locations
BR30 grow light bulbZ-GR-BR30-3SNot published — ask usE26 socket (screw-in)
9 W		Not published — ask usDamp locations
PAR38 grow light bulbZ-GR-PAR38-3SNot published — ask usE26 socket (screw-in)
25 W		Not published — ask usDamp locations
Clamp grow lightZ-GRCLP-3SNot published — ask usPlug-in
13 W		Not published — ask usDry and damp locations