Avocado Trees With Type B Flowers

Flower Behavior

• Avocado trees flower before producing new growth in late winter to early spring. Avocado flowers are yellowish green, appearing in panicles of up to 300 tiny blooms. The flowers are perfect, meaning they have both male and female organs. These two sets of organs do not function together. Type B flowers open to receive pollen in the afternoon and close in the evening. The next morning, the flower opens as a male and sheds pollen. Type A flowers receive pollen the first morning and shed the pollen the next afternoon. Planting both types of avocado allows for cross-pollination between the two types.

Self-Pollination

• In temperate climates such as California, southern Texas and Florida, blooming periods may overlap, allowing the tree to self-pollinate. For this to happen, the female phase flower must be open and ready to receive the pollen shed by the male flower. Pollen is usually spread by bees and hoverflies, but may become airborne in a good breeze. Self-pollination occurs when the airborne pollen reaches the female flower. Cross-pollination occurs when Type A and Type B flowers are open at the same time and the insects transport the pollen. While some avocado varieties are bred self-pollination, the most reliable method of pollination is to plant Type A and Type B trees instead of relying on chance. B trees instead of relying on chance.

Type B Varieties

• While standard avocado trees can grow 60 feet tall, Little Cado tops out at a diminutive 12 feet, making this avocado a good choice for small yards. This variety is available as a Type A or Type B tree or both, so check the seedling's label if you purchase the tree at a nursery or garden center. Miguel produces heavy fruit with green skins in late summer on a medium-sized, upright tree. In cold areas, consider Jim Bacon, which tolerates winter temperatures as low as 23 degrees Fahrenheit. This medium-sized tree grows about 30 feet tall and produces fruit from December to January. If you have room for a 40-foot tree, Fuerte produces thin-skinned, buttery-tasting avocados from winter to spring. The tree has a spreading habit, so give it plenty of room to grow. Patented in 1997, Don Gillogly avocado is a dwarf Type B tree that produces fruit twice a year. The fruit is green-skinned at first, but turns black when the fruit is ripe.

Cultivation

• Plant trees 30 feet apart and away from the house giving them enough room to spread as they grow. Plant up to three avocado trees in one planting hole saves space and paves the way for cross-pollination. Although avocados grow in partial sun, they fruit better beneath the full, direct warmth of the sun every day. Avocados grow best in loose, sandy or loamy soil best and require good drainage. Wait a year after the initial planting to begin a fertilization program. Use a balanced fertilizer and give older trees a little extra nitrogen.