Kniphofia Yellow Hot Poker – Var Yellow Hammer is an evergreen clump forming perennial with long thin sword shaped leaves. Flower buds emerge from the base of the plants in a shade of lime green but become yellow with age. Yellow hammer variety flowers in late winter through to early summer (November December) and will grow in hot summer sun all day. A great plant for the beginner gardener. You are buying one flowering size plant. The plants reach to a Height 40 Inches X Width 27 Inches if you let the plant spread.