(46-55 days. Misc. Varieties) Batavian (aka Summer Crisp / French Crisp) lettuces are the absolute finest group of lettuces to grow. They can be produced under cool conditions (like other lettuces); yet will still be standing long after other heat resistant lettuces have bolted. Pick leaves at baby size, or allow plants to head. Batavian lettuce can be harvested by removing a few of the outer leaves of the head; the plants will continue to grow and produce. Or you can harvest the entire large, gorgeous head all at once. Leaves are thick, juicy and flavorful. Batavian lettuces are extraordinarily heat tolerant.