Most cacti and succulents will tolerate long periods of drought but if you want them to grow and flower you will need to water and feed them in the growing season every 2-4 weeks.
Growing season starts in April when the daytime temperature regularly reaches 20 degrees. The night time temperature at this time is quite low but the plants like this and good growth is usually achieved at this time. Growth will slow in high summer but will pick up again in early autumn. You should stop watering and feeding your plants around the end of September when the day temperatures begin to drop below 20 degrees.
Winter rest is important and most cacti can be left completely dry but leafy succulents should be given the occasional drop of water to prevent shrivelling and keep the roots happy. If the plants are kept in a heated room during the winter months then you should give them a drop or 2 but growth at this time of year should now be encouraged.