It could take several weeks before you see blooms. If you have an organic fertilizer you might want to use that. Using a synthetic might get you lots of leaves and few blooms unless it's high in phosphorus, the middle number for NPK content. One thing I've found that encourages blooms is milk. Yup, the stuff folks put in their coffee. Just add a tablespoon to a half gallon watering can or add water to an empty container when you've used up the milk. The calcium and minerals seem to keep my houseplants blooming and is gentle to your plants like the organic fertilizers.
This is the best info I have for storing and caring for zonal (non-hardy) geraniums aka Pelargoniums.
When weeding, the best way to make sure you are removing a weed and not a valuable plant is to pull on it. If it comes out of the ground easily, it is a valuable plant.