Different plants prefer different types of soil, but in general, a good potting soil mix should be just fine for most plants. Sometimes, the top layer of soil in a pot becomes crusted over and hard, and this makes it difficult for the plant to drink in water. To prevent this from happening, use a fork or stick to loosen the top layer of soil. To minimize the amount of water evaporating from the tiny holes you poke, cover the pot's upper surface with cut-to-size coconut matting, which is water-permeable.
You can water most of your plants from your tap or hose. However, if you have particularly hard water, this may pose a problem for lime-sensitive plants, such as rhododendrons or camellias. Due to hard water's higher levels of lime, these plants may experience stunted growth, drop buds or flowers, or have their leaves turn yellow. Check with your local water company to learn the degree of water hardness in your area. Ways to cope with this problem include watering with rainwater, applying an acidic fertilizer when feeding plants or using a water-softening agent dissolved in a watering can. Water the roots, not the plant itself. Also, morning or evenings are the best times to water, as to prevent evaporation during the hottest times of day.