Welcome to container gardening. Much of your gardening experience growing in the ground will have to be relearned as you find it does not apply when growing in containers. You have found the right place for getting the help needed. The use of compost and compost tea and worm castings, though still useful will be used a little different. The leaves of your plants are telling you their needs are not being met. The container plant is completely dependent on everything needed being provided by the gardener, with no reserves being available from the ground. All you need is available on this site. Al

I always want to agree with gardengal but I seldom do. This time I DO! I had a Meyer lemon in a pot for years and finally pulled it out this past fall. When we got the tree it was blooming and had been cared for with synthetic palm tree fertilizer (I knew the former owner). I pretty much ignored it until 2002 when I went organic with everything. At first I only used corn meal on it. When I finally applied alfalfa, the tree grew 6 inches in every direction within 30 days. I think the tree/soil combination had a lot of pent up energy that was released with the alfalfa. I gave it a heaping handful of either corn or alfalfa every month that I remembered. That was probably about 6 times a year. We always got hundreds of blooms and about 6-12 fruit. Growing a citrus in a pot is hard because they like more of a consistent moisture level than I was able to keep up with. My schedule takes me away from home for weeks at a time, so it had to go into the ground. I also had 15 African violets that I kept organically. I got them for $0.50 each from Wal-Mart long after the season. They were outside in winter being watered daily. Needless to say they were in awful shape. Three died almost before I got them home but the other 12 recovered nicely. Two of them bloomed but again, my job changed and I was not able to pay attention to them. But I was able to do things to them that the African violet mafia would cringe at. Well, they would have simply passed up anything from Wal-Mart to begin with, but it made a great experiment for organics. My conclusion after that experiment was that by fertilizing with milk, the violets became bullet proof. They never got a fungal disease, leaves did not drop from stress, leaves did not discolor from water spots, or any of the other common violet problems.

How exactly do you figure seaweed or fish emulsion isn't organic? ;) And no, I wouldn't cut up your old sushi seaweed sheets (really biting my tongue on that one because it's seriously cracking me up, I find it pretty adorable). Whether or not your seedlings need more fertilizer than provided by the worm castings is really a pretty complex question, depending on what else is in the soil, what type of plants they are, how old they are, and how fast you want them to grow before you can plant out in your zone. Myself, I don't bother too much with extra ferts unless I need to stimulate growth or the plant is a heavy feeding variety, but when I do, I use a very diluted fish emulsion and only on mature seedlings (several sets of true leaves). It sounds to me like you've got the seedlings in some type of soil, ie not sterile seed starting mix that has no nutrients at all, so they're probably fine as is unless you have a reason to think they need more ferts.

You can brew worm tea but I have found a better method. It takes months to make worm castings. I have 5 worm bins made from Kitty litter buckets and 2 inside bins (rubbermaid containers). I have a lot of potted plants and hated tossing the spent potting soil (expensive) into the garden. I have 2 compost tumblers and when the exothermic reaction is done I add worms to speed up the process. All bins are raised and have collecting trays. The drippage is the best worm tea. I collect it daily using a turkey baster,bulb syringe, or toomey syringe if you have one. You can collect the tea long before the castings and pour it on your potted plants. I have a 5 foot cilantro that really loved it and have brought back many nutrient deficient plants. Recycling potting soil in worm bins really works too and the worms love them.