I have three dwarf fruit trees,how often do I need to water.

ho long have they be planted?Are they in the ground or in pots.what trees are they?

If they are in pots, at least every 3rd day -- and deeply. Make sure their roots don't sit in water. Happy gardening.

That really depends on the type of tree, your location & weather, etc. Are they newly planted? In ground or in containers?

They need more water than you might imagine. And here in CA where water is a precious commodity, how you water does make a difference. See if these help!

http://homeguides.sfgate.com/much-water-should-one-give-fruit-tree-48911.html

http://homeorchard.ucanr.edu/The_Big_Picture/Irrigation/

https://www.fourwindsgrowers.com/tips-and-advice/growing-dwarf-citrus/in-the-ground.html

And since you are so close to SLO, I would give Cal Poly a call, they have a great agricultural program and is a fantastic local resource! Lucky you! I would love to live where you do. 🌞

Newly planted trees need watered often, esp. in the heat of summer (2 days at most between) and give them buckets and buckets of it when you water. We have dwarf fruit trees too. If they are well established and have been there for several years, they may only need some during their fruit growing season. You did not say if they are new or not.

thye will need constant water at the temperature.water first thing in the morning,and if need be again when the sun starts to set