You can absolutely keep your herbs in plastic container pots. Assuming the herbs are still small, I would recommend 4″ X 4″ X 4″ square nursery pots. These will support your plants until they are larger and strong enough to withstand planting outdoors or transplanting to even larger containers. The larger the pot, the larger your herbs may become. Plastic nursery pots are great for growing herbs because they ensure adequate drainage via the holes in the bottom. You may water your herbs from the bottom by filling water catching saucers with water and waiting until the pots become saturated by wicking the water up throughout the entire container. If there is any excess water in the saucers after an hour or two you may dump any excess out. If you prefer to water from the top, water your herbs until water seeps out of the holes at the bottom of the pots and again, wait an hour or two until dumping that excess water out of the saucers. Basil and parsley prefer to stay moist, but not too wet, and should be watered every three days depending on the temperature and light they are receiving. To determine their moisture level just stick your finger about two inches into the soil and water when it feels dry to slightly moist. As for rosemary, it prefers to dry out more between watering. Water this herb about once a week when soil feels dry, again depending on environmental conditions. Happy gardening!
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