If you are talking things like Daikon and other winter radishes then you are right it is about time to plant them, I did so this morning. You can try the regular ones, but they do have a tendency to bolt in summer heat and may or may not form a "bulb", the best bet in the heat of the summer is a place with afternoon shade if you have it or can rig it up.
I went in to my seed store and asked for some radish seed. They were sold out. Not getting any more in till next spring. I will have to go look around some of the big stores that have nurseries? Teach me to stock up in the spring next year?
Gardening at 5000 feet elevation, zone 4/5 Northern Utah, Frost free from May 25 to September 8 +/- Plant a Garden
Yep, here in MD the regular spring radishes would just bolt due to the summer heat. I bought my radish seeds online as I want to try different varieties.
Dan - "Welcome back my friends to the show that never ends..." Emerson, Lake and Palmer - Karnevil #9