If your climate allows you to have fall plantings, then no problem! You can certainly use the seed from an earlier crop of the same year to plant again later on, as long as they had been harvested/stored properly. One thing you do have to be aware of is that if your bok choy was a hybrid, then its seeds may not come true, meaning that the offspring may not have the same characteristics as the parent plant. Planting in late summer will give you a fall harvest. Or, if your climate allows, you can plant in fall for a winter harvest. Be sure to keep soil cool and moist in the summer to reduce stress for these cool-loving plants and deter bolting. Good luck!
If your climate allows you to have fall plantings, then no problem! You can certainly use the seed from an earlier crop of the same year to plant again later on, as long as they had been harvested/stored properly. One thing you do have to be aware of is that if your bok choy was a hybrid, then its seeds may not come true, meaning that the offspring may not have the same characteristics as the parent plant. Planting in late summer will give you a fall harvest. Or, if your climate allows, you can plant in fall for a winter harvest. Be sure to keep soil cool and moist in the summer to reduce stress for these cool-loving plants and deter bolting. Good luck!