Tubular flowers are known to botanists as one of a group called sympetalous. This means that the petals are joined, either wholly, or partly. Hummingbirds are particularly attracted to tubular-shaped flowers, especially if the flowers are red. Scientists at Bellarmine University suggest that in the Jurassic period, the long, tubular mouth-parts of pollinating insects and birds evolved in response to feeding on tubular flowers. If you are planning on planting tubular flowering plants in your yard, get ready for a beautiful flower show and lots of birds and insects as well.
Popular in Texas gardens, the turk's cap is a herbacious mostly perennial shrub that will grow to a height of 4 feet. In warmer climates, it will bloom year-round with deep, red or white flowers that are twisted, like a turk's cap, and tubular. Turk's cap is drought-tolerant and grows well in the shade. A heat-loving plant, it is hardy in USDA Zone 7.
Another red-flowered hummingbird favorite is the scarlet salvia, also called red salvia. Native to Brazil, this plant is frost-sensitive but otherwise easy to care for. The striking, red tubular flowers bloom in clusters on tall spikes in the summer, and will last until the first frost. Scarlet salvia does like a moist soil so regular watering is important.
Cape honeysuckle can be planted in partial shade, although it prefers full sun. This is a very fast-growing shrub and is considered invasive in some areas. Cape honeysuckle is a low-maintenance plant that requires very little water once it is established and, in mild weather areas, will bloom all year. The flowers are tubular and bright orange. The cape honeysuckle is hardy to USDA zones 9a to 11.