A good time to fertilize new plants or any plant is in the spring or at planting time. I like to use a slow release plant food like Osmocote Plus as the nutrients are released slowly over the season so I don't have to think about feeding again. Osmocote is a general purpose plant food so good for all the plants you mentioned but can also be used on roses and edibles. As for watering, that depends on your soil type, sun exposure and temperature. In sandy soil in very hot areas watering every day or even twice a day might be needed. In a cool summer area like the Pacific Northwest (where I live) watering from a drip system just once a week until the plants are established could be enough water. A tip to deciding how much water is to poke your finger into the soil up to the second knuckle. If you feel moist soil about 2 to 3 inches down then do not water. Set your drip system up so that you can monitor how much moisture the plants are getting each time it goes on. Then you can adjust the timing as you figure out how your soil holds on to moisture and how the plants are looking. Don't worry, once you get over the first year of experimenting you will become an expert on just how much water your particular garden is getting from the drip system. Better to water too little than to water too much. Less supplemental water forces the roots of the plants to grow deeper in search of moisture making for more independent plants - and a lower water bill. Keep growing, Marianne Binetti