Vachellia cornigera, Acacia cornigera

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Vachellia cornigera, commonly known as Bullhorn Acacia, is an evergreen small tree that typically grows up to 10-20 feet tall. Native to Central America, Mexico, it is drought-tolerant and can thrive in full sun and dry conditions. Its foliage is typical of Acacias, with bright, tiny leaves and prominently spaced, prominent thorns. The thorns also serve to protect the tree from herbivores.

Its bright yellow, orange flowers, produced in spring and summer, attract nectar-seeking butterflies and hummingbirds. The plant is also highly decorative and can be used in gardens for topiary or hedges. As it produces fragrant flowers and can attract wildlife, it is a popular choice in the ornamental gardening trade.

Bullhorn Acacia is moderately adaptable to various soil types, but it prefers well-drained soil and is intolerant of moisture-retaining soil. It should be fertilized with a nitrogen-rich fertilizer twice a year, in spring and summer. It prefers a sunny site and protection from cold winds. In cold regions, it can be grown in large pots, which can be shifted indoors during cold periods.

In USDA Zone 8 through 11, Bullhorn Acacia is low-maintenance and makes an excellent addition to any landscape with its fragrant flowers, lush foliage, and attractive thorns. It is easy to grow and can be propagated from seed or cuttings. With minimal care, Bullhorn Acacia is a natural way to add a dose of greenery and bring a bit of nature to your garden.

Vachellia farnesiana, Acacia farnesiana, Mimosa farnesiana

Vachellia farnesiana, also known as the Yellow Mimosa, is a beautiful large shrub or small tree native to Tropical America. It reaches a height of 5-10 ft when grown as a shrub, and 10-20 when grown as a small tree. Vachellia farnesiana grows best in full sun to semi-shade areas with moderate water. This plant is a favorite of butterflies and hummingbirds due to its vibrant, yellow and orange flowers that are also sweetly fragrant. The puffs of yellow flowers give Vachellia farnesiana a beautiful look, while they also make it an ideal accent or specimen plant.

This plant can be grown in a pot in cold regions if kept like houseplants, as it is hardy in USDA Zone 8-11. It is a surprisingly tough plant and can withstand even quite cold temperatures for short periods of time, being mature plant cold hardy at least to 30s F. It is also pretty salt tolerant, making it a great option for seaside locations.

When growing Vachellia farnesiana, the soil should be well-drained and should be fertilized regularly. This bushy shrub can reach a height of 5-10 ft when grown as a shrub, and 10-20 ft when grown as a small tree. Pruning regularly and training it while young would be beneficial as it will help produce more flowers. When grown as a shrub, it should be pruned heavily at around 3-4 ft to promote branching and flowering.

To ensure a healthy plant, water it regularly and do not let it dry out too much. Mulching is also important to protect the plant from extreme temperatures and to prevent water evaporation from the soil. It is also essential to watch out for pests and weeds, and to be mindful of the quantity of water and fertilizer that is used to prevent any burn or damage to the roots.

Vachellia karroo, Acacia karroo

Vachellia karroo, commonly known as Sweet Thorn, is a small tree that grows 10-20 feet tall and wide. It requires full sun to partial shade exposure, and moderate water. The thick green foliage is adorned with yellow and orange flowers that attract butterflies and hummingbirds to the garden. Additionally, the thorns or spines make it desirable for providing a boundary and a safe haven for birds.

It is integrally part of Africa's history having been used for everything from raft-making to sewing needles and fencing for the houses of the royal Zulu women. The thorns were even used by early naturalists to pin the insects they collected. The Sweet Thorn tree also offers ethnomedical use. The bark is used in tanning and rope making, while the root is used in traditional medicine. Growing in USDA Zone: 9-10, the mature plant can be cold hardy to at least 30s F for a short time, which makes the tree well suited for cold weather climates.

When it comes to growing and caring for Sweet Thorn, the soil should consist of medium to water-retentive soil and well-drained soil. The tree tends to perform better when mulch is added, so it is advisable to mulch around the roots to help the tree retain moisture. During periods of drought, the tree can react badly and should be watered routinely to maintain its health. For those living in cold climates, caring for Sweet Thorn in a pot is perfectly suitable. It is important to place the pot in a location that is particularly sheltered and well-insulated.

Overall, Sweet Thorn is an exquisitely beautiful and highly versatile tree that adds beauty and medicinal value to any garden.

Vachellia oviedoensis, Acacia oviedoensis

Vachellia sieberiana, Acacia sieberiana

Vachellia sieberiana, commonly known as Paperbark Thorn, is a small tree native to the regions of South Africa. It grows in full sun and can tolerate moderate amounts of water, though it typically prefers dry conditions. Vachellia sieberiana is a cold tolerant species, thriving best in USDA zones 9-11 if grown in a pot.

This attractive tree can reach about 10 -20 ft in height and produces small yellow or orange flowers in autumn and spring. It has numerous ethnomedical and spiritually important uses, including being used to attract butterflies, hummingbirds, and other birds.

Vachellia sieberiana is easy to take care of and maintain, requiring little water, since it's a drought-tolerant species. It prefers light, well-drained soils, with plenty of mulch to keep the root zone cool and moist in hot weather. In areas that experience frost in the winter, it is important to protect young plants, as they may not be cold hardy until after two or three years of growth. A layer of mulch can provide cold protection.

Although Vachellia sieberiana can tolerate low water levels, it will only reach its fullest growth potential with regular waterings during dry periods. If grown in a pot in cold regions, ensure that you bring the plant inside before temperatures drop and provide a sunny spot indoors. A quality fertilizer suitable for woody plants should be applied at the start of the growing season, and again after flowering, to promote abundant blooms and lush foliage.

Vachellia sphaerocephala, Acacia sphaerocephala

Vachellia sphaerocephala (Bulls-Horn Acacia) is a large, graceful, evergreen tree that is grown for its interesting and attractive silhouette, paired with its yellow and orange flowers. This plant is indigenous to southern Mexico and Central America, but has a wide growing range, as it can be found in warmer regions close to the equator and as far north as the USDA zone 9-11. The trees are known to get quite big, with mature trees reaching heights of more than 20 feet, however there are varieties which come in at 10-20 feet that can easily fit in to smaller spaces such as yards and gardens.

Vachellia sphaerocephala requires full sun and moderate water, while in terms of soils they are not very picky, but are great in well-drained soils. They are quite drought tolerant as well, once established. While the trees roots can be deep and spread far, so great care must be taken when planting near any structures or underground utility lines or pipes.

Vachellia sphaerocephala's main care requirement is that it requires pruning to make it stronger. The tree is known to have long, thorny or spiny stems, which may impale any passers by, particularly if planted near walkways. It is important to prune heavily to encourage this plant to develop a sturdy and strong frame making it much less likely to break in strong winds or stormy weather.

It is quite easy to grow Vachellia sphaerocephala in cold climates in a container or pot. Simply choose a pot with adequate drainage that is big enough to accommodate the size of the tree. Ensure the pot receives adequate sunlight and the plant is given proper hydration and fertilization throughout the growing season. In cold regions, it will require bringing the pot indoors when temperatures start to drop below freezing. This will stop the tree from suffering frost damage.

Vachellia tortuosa, Acacia tortuosa, Mimosa tortuosa

The Vachellia tortuosa or Twisted Acacia grows well in full sun in well-drained, moderately moist soils and exhibits strong drought-tolerance once establish. Its growth rate is slow to moderate, reaching a size of 5-10 ft tall as a shrub and up to 10-20 ft as a small tree. This handsome evergreen shrub or small tree makes an attractive specimen in the landscape. Numerous butterflies and hummingbirds will congregate around its fragrant yellow or orange flowers.

For regions in cold climates, the Twisted Acacia is best grown in the warmer days of spring and summer in a large container that can be easily moved indoors during the winter months. When planting in a pot, use a mix of soil-based potting compost and sand, and position the shrub in a bright spot with access to plenty of light. Water the pot in sparingly: let the soil dry out, then water thoroughly. Re-pot the plant every other year into a slightly larger pot. Apply liquid fertilizer in late winter or early spring to stimulate growth and flowering.

For further protection during cold winters, provide the Twisted Acacia with extra insulation by draping frost-like fabric over the container and adding a thick layer of mulch. Pruning is not necessary but can be done after flowering to shape and size the shrub. Generally, prune back approximately one-third of the new season's growth.

Vachellia xanthophloea, Acacia xanthophloea

The fever tree is an attractive, semi-deciduous to deciduous tree approximately 15 to 25 meters tall and has an open, rounded to spreading or flattish crown which is sparsely foliated. The characteristic, almost luminous, lime green to greenish-yellow bark is smooth, slightly flaking, and coated in a yellow powdery substance. If the powdery surface is rubbed away with the finger it will reveal a green bark beneath. It has a slender to spreading, sparse, roundish crown of feathery foliage. The thorns are long, straight and paired.

This species occurs in groups in low-lying swampy areas. Because its range coincides with regions where malaria is prevalent, it is called "Fever Tree."