We have grown this South American native for 16 years, during which time it survived 0 degrees F with only a little tip burn. Even more impressive is that it has survived Zone 6 temperatures when kept dry in winter at the Denver Botanic Garden. Caesalpinia gilliesii has woody stems adorned toward the top with lacy, grey-green, mimosa-like leaves. Topping each stem, starting in June (NC) are stunningly indescribable flower heads composed of bright yellow petals with contrasting red stamens resembling long red threads emerging from the flower. Caesalpinia gilliesii is sure to draw both visitor stares and rave reviews.