Last Sunday many of my cuttings graduated from moss to cups.

I have a grow light over the cuttings. For those who do similar, how long do you leave the light on? 24/7 or do you turn it off at night?

How often do you need to water them? The mix I put them in was barely wet - basically just moist. Not heavy with water at all. I'd hate to kill them with love (too much water) but don't want to dry them out, either...

Here are a couple of pics of the set up. Some I used peat pots, some I didn't. Just experimenting a little to see what works for me.

I move  mine under the lights after they've rooted and have been doing it since last year and the cuttings don't seem to mind being under the lights 24/7.

I would suggest 14-16 hours/day under lights. On watering there are to many factors to generalize. I think you just have to watch them look for the mix lightening and moisture on the cup. I always struggle with moisture and seems I have to gauge each one different depending a lot on leaf development as well as the root development. Don't treat each cup the same, some may need water when other do not

Ditto for Strudeldlog. I have a timer for my lights (T8's) and it is on from 7am until 7pm daily. 

I've been doing 13 hours of light per day with good results.

I do 16 hours on, 8 hours off using a simple timer available at your local hardware or home improvement store.  I'd say that with your setup (which is nice by the way), with the cups on top to slow down the moisture loss, you will not have to water very often.  Strudel is right that each pot will be different depending on root development, etc.  If you see little moisture droplets on the inside of the cups, then you probably don't need to water that day.  If you have the patience, you can use one of those misters for watering.  You're less likely to overwater with them, or to create a situation where the top is dry and the bottom is soggy.

I turn my lights on when I get up in the morning and turn them off when I go to bed. About 15 hours a day. I like the growth and green color this schedule has provided. Less light will probably work to.

Greetings

I was reading about the optimum number of hours of sunlight contrasted with darkness for growing plants and came across this bit that FFF members might deem beneficial:

Photoperiodism

The relative length of day and night and the seasons is important to plants. The number of hours of darkness in a 4-hour cycle is an important factor in determining blossoming and growing time.
Night length triggers seed germination, tuber and bulb formation, and other growth characteristics such as colour, enlargement of leaves and stem size and shape. This rhythmic characteristic is called photoperiodism and is of great value
to growers.

Plants can be classified according to photoperiodicity.
 Short-day (long-night)
 Long-day (short-night)
 Indeterminate or day-neutral

The perennial Chrysanthemum and the Poinsettia, which flower in the autumn, are examples of short-day (long-night) plants. They fail to flower when the day length, or period of light, is extended beyond a critical value.

Long-day plants, such as the China Aster and Tuberous Rooted Begonia, flower only with a day length longer than a critical value.

Day-neutral plants, such as the Rose and Carnation are not limited by photoperiod.
Understanding these principles enables commercial growers to use artificial light profitably, so that flowering and vegetable harvesting can be timed for markets.

For those interested, here is the URL where the above was extracted from
http://www.gelighting.com/eu/resources/literature_library/product_brochures/downloads/Horticulture.pdf

Plants do better without 24/7 lights... but that is what I use. I don't have a timer and I am not regular with respect to coming and going. And when I was turning the lights on and off, I would sometimes jsut forget. So now, I leave them on all the time and the cuttings are doing quite well.

I also like them on all the time since the cuttings are in a small unheated room (inside the house), and the light itself keeps the room warmer, esp at night. The temp now is constant at between 70 and 75*F. I use a generic, cheapo shop light with double, long florescent bulbs. It was about $12 at a big box a few years ago.

I also keep my cuttings (in separate 'cups' - I'm currently using free-standing plastic bags with lots of holes punched for good drainage) in a glass-covered bin. Not tightly covered so there is some air circulation. I mist almost daily, and sometimes water (a tablespoon or two) when the mix seems too dry. But watering is infrequent and judged by touch and 'weight', and not all of them get watered.

This is my second year rooting figs and while I had good luck last year, it's been even better this year.

I remember seeing someone's plastic bins being covered with plexy glass and I've often wondered where the heck they got that. That would definitely be a lot easier than these individual cups.

I have more cuttings that will be graduating soon and I have very little room left under that light. I think I'm in the market for another light now. Surfing craigslist as I type this (lots of pot stuff on CL - heh)

Right now the cuttings that have many roots and leaves have been removed from the rooting chamber and are under 8 hours of light a day. As the season progresses I'll increase the length of artificial light to match the natural sunlight by the time I set them outside in 1 gal pots. Plants need a time of darkness, especially young plants so they shouldn't be under continuous light.You're forcing these poor little guys to grow and grow 24 hours a day week after week with no natural daily rest. That puts a lot of stress on them compounded greatly if not enough fertilizer is given.

I think it's a hassle to double cup with a dome and harder to maintain a constant . I don't use plexi-glass I just use cheap 4 mil plastic  to tent over. I keep them in bin with the lids off. the the 4 mil plastic does need support, but while they are short  you can just lay some mini-blind slats or similar across the top. You can build a support for the plastic real cheap with PVC pipe and a few fittings. Don't bother gluing the pieces together the fittings fit together snug enough. when done pop apart and it stores easily and compact. I saw your Dog Agility pictures. I built most of my Daughters course out of PVC. Light, portable, durable, and cheap.  If you want go to the your Lowes garden center buy a couple plants unroll a section of the plastic (if it is the clear stuff)  they have at the exit to protect your care and while very thin will work as a humidity dome.

When my 20 cuttings were transferred to 1 gallon nursery pots they lived on a tall bistro type table near a south facing window.  Blinds were opened all day but when I got home it was usually dark so I turned on a Phillips screw in grow light (bought it at Lowes or WalMart).  That light was on about 3-4 hours a night.  This seemed to do OK for me but I am fortunate that I have a short winter to nurse the cuttings through until they go outside for sun (which was last weekend).  I'm sure my method wouldn't work for longer northern winters or winters with few sunny days.