If your question is only about how to water/feed in their fabric pots, since that's all I use (fabric) I'll tell you what I do... and I'll limit it to plants that are of the size I sense yours are now. I take a gallon of water/nutes and I pour about half of it into the pot... when it disappears, I put the rest of it in. If some of it comes out the bottom (or sides) and pools in the saucer, I leave it there for about 10-20 minutes to see if it will soak back up into the soil. If it does, I add even more. When finally the water/nutes are not being soaked back up, I empty the saucer knowing the soil is COMPLETELY watered/fed and go about my business... until the pot is super light which tells me it needs something more.... water/feed/water/feed
Good luck!