I planted 4 dwarf bean plants from seeds. It's been three weeks and they were doing pretty well. Recently I've noticed that the tips of the leaves are drying out and curling inwards, or tearing at the edges. I have been watering these plants but I'm conscious of overwatering. About two days ago I gave the plants some diluted hydroponic fertilizer. I also examined the leaves and couldn't see any pests. The climate where I am is similar to California. I would love to save my bean plants and any help will be so appreciated!