Keep picking! If you let cucumbers or squash, beans or any other vegetable over-ripen - producing seeds - the plant will think its work is done and stop producing flowers and setting fruit. Replant peas, beets, green beans and lettuce and you’ll have a new crop in September. In late August, remove flowers from tomato plants. There’s not enough time for them to set fruit and ripen before frost. And. removing new flowers tells the plant to devote its energy to growing and ripening the fruit already in the vine.