Lantana

Identification and origin

Lantana camara belongs to the verbena family, Verbenaceae. Its native range covers Mexico, Central America, the Caribbean and northern South America, from Colombia and Venezuela to Ecuador, Guyana and northern Brazil.

It is a small shrub, evergreen in mild climates, with woody stems but a sprawling habit, often wider than tall. Depending on the cultivar and the climate, it grows 12 in to 6 ft tall and 3–5 ft wide. The stems are square in cross section and sometimes carry small spines. The leaves, opposite or whorled, are oval, toothed, rough to the touch and 3–6 in long; when crushed they give off a strong, pungent scent.

The small, tubular, five-lobed flowers form domed clusters about 2 in across. They change color as they age, so a single cluster often combines yellow, orange, pink, red or purple. Bloom runs from midsummer until frost and draws butterflies, hummingbirds and other pollinators. It is followed by small fleshy drupes that turn metallic blue, then purple-black, and are eaten by birds.

In tropical climates, lantana has escaped from gardens and become a weedy, invasive pest. Choose sterile cultivars, which set little or no seed.

Light

Full sun is essential: at least six hours of direct sun a day, ideally eight. Light is what makes lantana bloom. In shade or part shade, the plant stretches, flowers sparsely and becomes prone to powdery mildew, the white coating on the leaves.

It handles heat, humidity and even salt spray at the coast very well.

Watering

After planting, keep the soil lightly moist for a few weeks, until the roots spread into the surrounding soil. Once established, lantana tolerates drought, but a long dry spell cuts back growth and bloom.

The useful cue: water when the top 1–2 in of soil feels dry, then soak the whole root ball. In containers and in hot weather, the mix can dry out within a day, so check it daily in summer. Water at the base without wetting the foliage to limit disease.

Too much water is more dangerous than too little: soggy soil reduces flowering and eventually leads to root rot. Containers must always have drainage holes.

Potting mix

Lantana accepts almost any soil as long as it drains well, ideally slightly acidic, with a pH of about 6 to 6.5 and plenty of organic matter. In heavy soil, work in compost or sand to improve drainage. It also tolerates poor and salty soils.

In containers, a standard bagged potting mix works well. Lantana often does better in a container than in the ground, thanks to the sharper drainage.

Go easy on fertilizer: a balanced fertilizer at planting time, then perhaps a light dose in midsummer. Excess fertilizer reduces flowering and makes the plant more prone to disease.

Temperature

This is a heat lover: set it outdoors only once the soil is warmer than 61 °F, at least two weeks after the last frost. Even hardy types are slow to start growing in spring and wait for truly warm weather.

In the ground, lantana behaves as a perennial in USDA zones 7 to 11. A few cultivars such as ‘Miss Huff’, ‘Ham and Eggs’ and ‘Chapel Hill Yellow’ are hardy to zone 7b. Elsewhere it is grown as an annual or overwintered under cover.

To keep a potted plant from one year to the next, the easiest approach is to let it go dormant: place it in a room at 50–61 °F with little light, and water just enough to keep the root ball from drying out completely. Keeping it in active growth indoors is possible, but the weak winter light leaves it spindly. Do not let it drop below 50 °F.

Repotting

Plant or repot in spring, when the plant comes out of dormancy and temperatures rise. Choose a container with drainage holes, only slightly larger than the root ball, filled with a free-draining mix. In beds, space plants about 12 in apart, more for vigorous spreading types.

Lantana grows quickly and aggressively, so give it room to spread without smothering its neighbors.

Pruning

In summer, lightly shear the tips of the stems and remove spent flower clusters: the plant responds with fresh blooms. A plant loaded with berries flowers less, and a light trim gets it blooming again.

If a plant outgrows its space, it can be cut back by up to a third of its height and spread during the season; water it, give it a little fertilizer, and it will soon rebloom.

Perennial plants in the ground are cut back hard in spring, to 6–12 in above the soil, to remove old growth and keep them from getting woody. Avoid hard pruning in fall, though, as it reduces cold hardiness.

Propagation

Cuttings are the usual method. Take a stem with no flowers, about 6 in long, strip the leaves from the lower half and stand it in a glass of water. Roots appear within several weeks, and the cutting can then be planted in soil.

Division and seed are possible too, but many cultivars are hybrids with trailing lantana (Lantana montevidensis), and sterile cultivars produce no seed.

Common cultivars include ‘Miss Huff’, orange, coral and gold, vigorous and sterile; ‘New Gold’, low and spreading, golden yellow and sterile; ‘Chapel Hill Yellow’, compact and cold hardy; ‘Radiation’, red-orange, 4–5 ft tall; ‘Samantha’, with variegated foliage; and the compact Bandana and Little Lucky series.

Common problems

• Sticky leaves that turn black (sooty mold): usually whiteflies on the leaf undersides.
• Grayish, stippled leaves that brown and drop: lantana lace bugs.
• Dull leaves with fine webbing: spider mites, especially on a plant kept too dry or overwintered indoors.
• White coating: powdery mildew, encouraged by shade and poor air circulation.
• Wilting despite moist soil: root rot from poorly drained soil or watering too often.
• Few flowers: too much shade, too much fertilizer or a heavy crop of berries.
• Chewed leaves: caterpillars.

A symptom can have several causes: look at all the growing conditions (light, watering, drainage, air circulation) before drawing conclusions.

Toxicity

Lantana is toxic to dogs, cats and horses. It contains pentacyclic triterpenoids, lantadenes A and B, found in the leaves, flowers, berries and sap. Eating it can cause vomiting, diarrhea, labored breathing and weakness; liver failure is seen mainly in livestock such as cattle, sheep, goats and horses.

It is also hazardous to people, especially children: keep the berries, above all the green ones, out of their reach, since eating them in quantity is the main concern. The foliage can irritate sensitive skin, so wear gloves when pruning. If any part is swallowed, contact a poison control center or a veterinarian.