Alicia Bannon

That sounds like a worthwhile experiment, especially in zone 9B. Keeping the seed bed consistently moist is probably the biggest challenge with summer-sown carrots, since the seeds are so small and can dry out quickly. The board and vermiculite seem like a good way to help with moisture retention and germination. I'd be interested to hear how the roots turn out, though, because the summer heat could affect both growth rate and flavor. If they do well, having fresh carrots available year-round would definitely be worth the extra watering.

I've had similar experiences with squash doing surprisingly well in rich organic material. I think the key is probably the overall soil biology and moisture rather than simply having lots of nitrogen. I like using compost, aged manure, and plenty of organic matter, but I try not to overfeed once the plants are established. Consistent moisture seems to make a huge difference for squash in particular. A thick organic mulch has also worked well for me, keeping the soil cooler and reducing how quickly it dries out. I think gradually building fertility and letting the soil biology do its thing works better than constantly feeding cucurbits.

I've had pretty good results with keeping spider mites under control by regularly checking the undersides of the leaves and catching the problem early. If I'm not sure what I'm looking at, I sometimes use a plant identification app to take a closer look at the symptoms. https://botanapp.com/identifier/houseplants can identify plant problems from photos and provide care suggestions, which can be useful when you're trying to figure out whether you're actually dealing with mites or something else. I still prefer to confirm the diagnosis before treating, though.