As suggested, I'm adding blog post below to "forum"..still need to learn how best to use this site.Thks.
Can anyone advise what the difference is between using Dow blue boards and the white 2" styrofoam at Home Depot. Do the dow blue boards need to be painted? I don't know if I would ever try to be "Certified Organic" but I would want to do what is safest.. Does it make a difference? Thanks.
It is my hope to come up with more information as to type of material, manufacturer, and a place to buy this raft material in sheet or roll form, without the holes precut, which means the spacing and size of the holes would be up to the individual.
With regard to planting out your seedlings, it would depend a lot on the method and medium you are using to start the seeds. Many videos show the net pots being dropped into hopes in the rafts, with whatever loose medium there is being rinsed off to keep as much as possible out of the beds. If the starters are in trays with soil, perlite or such, again they show most of that medium being washed off the roots, and in some cases simply dangling the roots through the holes, in which case it would be good to have different sizes and spacing for different stages of growth, or use something inventive for spacers, initial propping etc.. This is where some of the more experienced growers would have more details.
How many holes per 4' x 8' raft, realizing that the end pieces may be much smaller, for starting lettuces, leafy veggies etc then how many for growing them to harvest? I know I seen some good pics or a YouTube video somewhere but can't seem to find it. Thanks.
Ok, here I go on a new experiment!
I now have a big raft bed to experiment with. Well it's not plumbed in yet and I notice the used billboard liner leaks a little where small abrasions or pin holes have damaged it but are for the most part too small to really see. Not sure if it will work long term but I'll try testing it out for a bit, I can always turn it into a bed wicking bed for dirt gardening if I decide the raft method doesn't work for me.
So does anyone know exactly what kind of paint is food safe for the rafts?
I'm going to experiment with a few different possibilities for rafts. The bed is about 36 inches wide so I figure a 32 inch wide raft would be appropriate which is conveniently an 8' long board cut in thirds. (the bed is long enough for six 4' long rafts at that width.)
I'm still a big fan of using rayon mop string wicks in net pots to allow for starting seeds directly in net pots and I've also found that a peat pellet dropped onto the wick in a net pot will stay moist enough to keep a seedling going till it's roots reach down to the water. I've found that the peat pellets stay nicely moist using capillary fabric with an end hanging into a trough of water so this is a great way to start lots of seeds in a small shelf space. I'll be testing other seed starting methods on the capillary fabric as I can.
I do like the idea (in my system since I've got plenty of bio filter and solids filter in my grow beds) of suspending the rafts above the water so that I don't need to add lots of extra aeration to the beds. However, my bed construction won't support too much weight on it's edges or allow for easy sliding of anything resting on those edges so I still need to figure some way to FLOAT the plat supports. I might try a square of sealed up PVC pipes to support a board with holes. I also want to sort out some way to float the rectangle seed trays for growing baby salad mix ans such (this sort of use might be the most useful to me.)
Looking for other creative ideas too.