Answer: Radishes grow best when sown when temperatures are cool; very early spring or fall crops develop fully. When growing in the summer, all the energy is directed into top growth. Wait until September and you should have better results with your radishes.
Pepper plants can drop their flowers if the temperatures are above 90F or if there is no insect activity (lack of pollination). There's not much you can do to change the weather. The good thing about peppers is that they produce flowers all summer long so you should see some fruits forming eventually.
Best wishes with your garden!
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