I am setting up an indoor area to germinate rose seeds. What kind of light bulb should I be using please?
(Having them next to a sunny window is not an option.)
Thank you.
You don’t need a light to germinate rose seeds, but you will need light to grow the seedlings. I don’t know where you are, but here in the US the most cost-effective light for most of us is the 4-foot utility light with 2 T8 (1 inch diameter) fluorescent cool white tubes and an electronic ballast. I like the kind with the “bat wing” reflector, but you might find another kind more useful. The “strip” fixtures that mount directly on something (like the ceiling or the bottom of a shelf) are much less expensive than those that come with reflectors. You’ll need to have the height of the lights adjustable so you can keep the lights down very close to the seedlings, or you’ll get poor growth.
T5 tubes are more efficient and have a higher output than T8, but the initial cost is much higher, and you’d have to run the lights a long time (years) to recover the cost difference. By then, the tubes would burn out and T5 tubes cost a lot more than T8 tubes, so you’d be paying more again.
If you can get some of the old fluorescent fixtures which had magnetic ballasts and used T12 tubes (1.5 inch diameter), you can retrofit them for the T8 tubes by purchasing and installing replacement ballasts (very inexpensive on eBay if you are buying several). The T12 and T8 tubes use the same socket, but it is necessary to change the ballast (transformer). The most cost-effective tube is probably the 4100K Cool White Octron. It has pretty good output in a range usable by the seedlings, is rated to last 24,000 hours, and can often be bought by the case for major discounts in home improvement stores. Or in smaller quantities, you can probably find them for about $2 each.
Peter