Many kinds of desert plants exist, from cacti to succulent plants. Desert plants typically store water in their leaves and stems, and use that water as needed. While each individual desert plant is different, there are some general watering guidelines that apply to most. However, it is always best to research your specific desert plant and its natural environment. In addition, remember that as the seasons and weather change, so does the frequency with which desert plants should be watered.
Set a schedule to check the desert plant's soil condition. Usually, every two to three weeks will suffice. However, take in consideration that you may need to check the soil more often during the growing season (usually from March until October) and during extremely hot and dry weather; this includes indoor plants during the winter months when the heat is on.
Check the soil for moisture. Simply stick your finger in the soil, about an inch deep. If it is dry, it's time to water your plant.
Water your desert plants--in the morning or evening hours are best, if possible. Water slowly and only as fast as the soil can absorb the water. If your desert plants are planted in pots, water enough so that the water drains out the bottom. Toss out the extra water. If your desert plants are outdoors, water slowly and only a couple inches. Evenly apply the water at ground level and under the entire canopy. Use a garden hose with a shower setting, if possible.