The John Dourley manzanita is well adapted to normal winter rains and periodic summer irrigation. Established plants grow well with periodic deep irrigation in the summer. Manzanitas are vulnerable to disease problems when summer irrigation produces moist soil and leaf litter conditions that enable active fungi and bacteria growth. The chart shown below provides a recommended baseline guide to the monthly irrigation schedule and volume of supplemental water needed to maintain healthy growth throughout the average year. It should be noted there are several months marked by an asterisk (*) when winter rains can provide sufficient moisture and irrigation is not needed. The high and low range of moisture indicates it can grow with varying amounts of water; it is desirable to have leaf litter and the top layer of soil beneath the stems to dry out between irrigation applications.

For more information on how to use this Irrigation Schedule and Graph, follow this link.

For information how to calculate your irrigation system’s schedule and precipitation rate, please follow this link.