Hmmmm...Hebes generally are from New Zealand and enjoy the climates of say Santa Cruz and San Francisco--cool summers, overcast, rain, fog...

I have not seen many that are successful in hot summer climates. Around here, they are not that easy to grow away from the immediate coast. Moist, rich soil. Most are not drought-tolerant plants.

Just my own experience, I am sure someone will have a better answer for you. I think though it will fry in full sun in Stockton.

Hebes are subject to fusarium wilt in California. I think they are difficult to keep alive in areas with that fungus in the soil. That said, if you don't have fusarium wilt, I would plant it in the ground again so the roots don't get too hot in the black nursery pots. They don't like too much heat. They seem to do okay in areas like Santa Barbara.

I'd suggest starting over with a new plant and plant it where it has a north exposure with just a bit of limited direct sun in early morning or late afternoon. As others have said, they don't really like heat or hot sun, and do best in the fog belts or sun which doesn't bake in summer. They thrive in areas with summer fog and drizzle.

I'd suggest looking for plants you like that actually thrive with summer heat, Gardenias, as one example, you can grow them there, we generally fail with them near the coast.

Your Kalanchoe beharensis is another plant that won't much like your winters as a plant in the ground. If that spot against the wall is also protected from getting drenched with winter rains, you might get it to grow; otherwise I'd suggest it as a movable container plant, and bring it indoors during the coldest/wettest weather.