By Phran Novelli

PHILADELPHIA (CBS) - Hey what happened? Your parsley and cilantro are suddenly two feet tall with flowers! What did you do wrong? That’s what a listener named Lisa was wondering when she wrote to ask about her herbs last week. It’s nothing you did and there’s nothing you can do but blame the weather – it just got too hot.

Some herbs love the heat, but other plants are just not meant for temperatures over 80. When plants like cilantro and parsley and lettuces get too hot, they simply go to seed to ensure a new generation. This behavior is called bolting, because the plant shoots up a stem a foot or two above the plant to put out flowers.

At that point, you can’t stop it but you can wait until it flowers and let some of the seed heads drop into the pot to grow new plants, and/or harvest them and start some plants indoors or in fresh pots outdoors. They’ll grow well when it’s cooler – usually late August until frost. Some people plant seeds of these heat-sensitive herbs every few weeks to have a constant supply of parsley for pesto and cilantro for salsa all summer long.