While there are many garden styles and countless ways to approach garden design, I think most people would agree that a mix of forms, colors, and textures produces a more interesting display.
With fall not far off, you might want to consider some plants that will not only add fall color, but bring some drama with their tall spiky leaves. The following plants are all classified as perennial, but are only reliably hardy to zone 8 and are generally treated as annuals in our area.
Dracaena difussa
Bronze Spikes
You are probably aware of the green version of this Dracaena that is available in the spring, but this variety brings a completely different color. With its long, bronze, graceful leaves, this accent plant is perfect for mixed containers. It grows 24″-36″ tall in full to part sun and is often winter hardy. Be sure it has well-drained soil and give it moderate water.
Pennisetum (Fountain Grass)
Black Stockings
This stunning large grass features bold purple leaves and canes with a bluish-green hue. Sterile black flowers appear in late summer and fall. Fountain grass is dramatic at the back of the garden or in seasonal color plantings. Give it full sun and keep evenly moist. Although usually smaller, it can grow 5-6′ tall by 2-3′ wide.
Phormium (New Zealand Flax)
For an attention getter in your garden, it’s hard to beat Phormium. These plants are great in containers, beds, mass plantings, and look perfectly at home in waterside plantings. Plant them in rich, moist soil in full sun to light shade. Water regularly until established, then water moderately.
Sundowner has bronze-green, spiky, strap-like foliage with pink new growth. With an upright habit, it can grow 6-8′ tall by 4-6′ wide.
Platt’s Black has chocolate brown, arching, sword-like leaves and a clumping habit.