You could try partial shade and mulch

I think they are a cool season veggie. Agree, shade may help. We are in your same zone and it's too hot here for tomatoes to set, except the cherry ones. We just planted okra, eggplant, pumpkins, watermelon, radishes, and black eyed peas. They seem to be more heat loving.

I can only speak to my climate which is definitely not hot and dry at any time of year. Sprouts are sown in spring, planted out in late spring early summer and then harvested in the cooler months, ie from October to April. Although eaten in the cooler months they have a long growing season and need planting in warmer months. (Warm by our standards would be around 60 - 70f.) The flavour is much improved after they have had a frost on them. This link give info. for the US. What is the friend who gave them to you doing with theirs?

Here in the Carolinas I don't know anyone locally who can get them to grow, and this was even in the fall. It's really too warm here. Ours grew about a foot tall, and we got teeny tiny sprouts like pea sized.

I just found a new technique I am going to try this year.

Start the seeds indoors in hot dry June, July and August for planting in September, hopefully I'll have them for the holidays. FYI I successfully grew them outside last year but they take forever.

If she gave them to you in April they may have been good by September. Did you ever give them a shot. I would think they would do well fall in Cali with the cool nights.

They do take forever, especially down here in the deep south. I have one plant right now that was planted in Nov 2015 that won't be ready for a month or so...

That is very intriguing, Brad. Where do you live that you are planting in November? Sprouts are biennial so a plant sown in 2015 should have bolted in 2016, after which it would normally be useless for producing sprouts. Can you show us a picture?

That was a while back and I don't take pictures of my vegetables lol. I have had the same things happen more than once, so it wasn't an annual occurrence. Most gardeners here don't try them. I like to keep them in semi shade to get that extra summer growth. Sadly, I had my chickens get into mine this summer and decimate them... so maybe if I am not too busy in a year I will make a chicken free garden for stuff like this.