Yellowing seedling leaves is almost always a sign of too much water. So either you are over-watering - which is the most likely cause - or the soil is very poorly draining. Either way, try cutting back on the water and see if they don't pick up. Work your hand deep into the soil to check for moisture before watering. Don't go by the appearance of the top layer.

You might also want to give them a 1/2 strength dose of some balanced liquid fertilizer or work a good amount of some time-released fert into the soil around them. Nutrients leach out of containers - and a raised bed such as you have is really just a big container - every time you water so they must be replaced more often.

Hope this helps.

Dave

If you notice a difference with Dave's 1/2 strenght dose of balanced liquid fertilizer recommendation, it might also be that the redwood chips are pulling the nitrogen out of your soil and that this may not be an issue for the fava beans.

I built a raised bed at my girlfriends place this year. I also brought in a soil/cow manure mix. I noticed that the mix would crust over making it hard for seed to sprout through. I fixed this with store bought compost worked into the top inch or two. The second seed planting did just fine sprouting. I think I did this on advise from digdirt Dave. I fertilized much as he has told you here. This is the first time I have been able to grow mature pumpkins in this sub arctic area of Oregon.
I hope this helps,
James

Thanks guys. I was thinking the same thing about the crusting over of the top layer of the soil. The seeds still sprouted, but it took longer than expected. I'm gonna add some compost to the mix and see if that helps. I'm also going to try and fertilize with some half strength fish emulsion tomorrow to see if the theory about the redwood shavings rings true. Now, let me understand this correctly.... since favas fix their own nitrogen, they would be unaffected by a possible nitrogen deficiency in the soil right? and yes Dave, I'm pretty sure I'm watering too much. Soil is soaked down about a foot deep. But, it rained a bunch in the last 48 hours too. One of my beds has a different soil mix (store bought topsoil and store bought compost) and besides what seems like a sow bug revolution that has massacred my peas and kale seedlings, this bed is producing well with chard, tomato, lettuce, and a couple kale survivors. So, maybe the soil in the other boxes just doesn't drain as well as this productive box? And, since I'm on the subject, what to do about sow bugs? They are seriously jacking my garden up!

I'm also going to try and fertilize with some half strength fish emulsion tomorrow to see if the theory about the redwood shavings rings true.

If fish emulsion is what you are using for fertilizer then you don't have to use it half-strength as it is low-nutrient to begin with. You'll need it full strength to try to off-set the nitrogen binding by the shavings. Better yet would be some sort of high nitrogen supplement. If you only want organics then use alfalfa pellets.

they would be unaffected by a possible nitrogen deficiency in the soil right?

That is basically correct. While beans won't tolerate soil that is totally nitrogen-deprived, they will tolerate low-nitrogen conditions with no problem. Beans in high nitrogen soil just make huge plants but no beans.

As I said above, raised beds or 'box' beds are basically just large containers - at least for the first few years - so they benefit from being treated as such. Adding lots of loose soil-less potting mix and more feeding than one would an in-ground bed can be of great benefit.

Sow bugs aren't normally a real pest problem but crop damage by them is a good indicator that the soil is too low in organic matter - their normal diet. But if you find them to be overwhelming, any of the slug baits available such as Sluggo will help control them.

yes Dave, I'm pretty sure I'm watering too much

You aren't alone - most home gardeners do. They forget that roots need air even more than they need water. It it is a hard habit to break. Tape a sign to the faucet "Kills Plants" and picture that hose as a snake. :^)

Dave

Diatomaceous Earth should help with the sow bugs. DE is found in most slug control products, but there may be other unwanted ingredients in those products. Check the label before you buy.

Here is a link that might be useful: sow bug info

I would agree it sounds like it's too moist. I would dump a few bags of washed sand in with the beds for better drainage and turn it thoroughly (with some blood and bone meal) and see if you can create some better soil structure. 50 lb bags are cheap at any Home Depot or Lowes.

So, two of my three raised beds are still hurting. The favas in one bed are about 5 inches tall after about a month and a half from sprouting. the leaves are yellowing a bit, but the plants are getting blossoms. I think they should be bigger. The other bed had kale and collard green seedlings as well as carrots and radishes. As I mentioned in earlier posts, everything went yellow and died. I'm starting to wonder if the planting mix I loaded the boxes with needed to be mixed with the dirt in my yard instead of just being by itself. Wondering if it would just be better if I removed the boxes and dug the planting mix into the dirt below and started over. Your thoughts garden homies?

You might want to do the tried-and-true soil analysis to see where you stand.

Your theory on what's wrong might be on target. However, taking down your boxes and mixing sounds like a bit of a project to me. If you have room in the bed to mix in a 2 to 3 inch layer of topsoil with the mulch then that might suffice. Also, have you tried adding urea nitrogen to the bed (something along the lines of 34-0-0)? If not, this along with the topsoil addition might help.