What's the proper way to water a rosemary plant is a common question asked by those who have culinary plants in their garden. This is one of the edible herbs that enter in various delicious recipes. The rosemary plant is considered one of the drought tolerant and drainage sensitive, hence if not treated well can die from either rot root or excessive drought.
If planting the rosemary in a container or pot, make sure you water it frequently in the first few weeks until it establish a good root system and start giving the green shoots. At this stage you can slow down on watering and water only when the surface soil feels dry. Make sure the container is well drained on the other hand to avoid the rot root problem. Organic soil for edible herbs is a good idea as well. On the other hand, if planting it on the ground, you will probably not need to water if it rains few times a month, otherwise one watering a week in drought conditions should be sufficient. This is also true only after the plant has developed a good root system. Make sure the ground is not vulnerable for pooling of water but well drained otherwise the roots might die.
To conclude this post, one of the important things to notice is that the rosemary plant might die couple of weeks before it show any signs, a frustrating fact but good to know that you are dealing with a special plant of its kind. It might be helpful using something like this soil meter for a more moister control.