I don't know.
I think 30 to 40 days.

My female hasn't laid yet, male was introduced on Friday before Easter so copulation could have happened anytime since then, I witnessed it on the 16th.

This is her today - I think she's gravid, but if she hasn't laid by the 31st the male goes back in.

You can see she's been digging by the stuff on her back
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3.6 L. getula californiae - 19 eggs (Cal. King)
1.1 L. getula nigrita (MBK)
1.0 Pantherophis guttatus guttatus (Corn)
0.1 Pituophis catenifer catenifer (Pacific gopher)
3.3 Elgaria multicarinata multicarinata (Cal. Alligator Lizard)