Filbert likes as least half-day sun and good garden soil. A harbinger of spring, male catkins elongate 2-3 inches and release puffs of pollen. The female flower is slightly bigger than the head of a ballpoint pen. Excellent red, yellow, and orange fall color. ... Many people tell me their filbert never produces seed. All filberts will produce seed, although you have a better chance if you have 3 or more plants.