Lantana is really a tough-guy in the garden here in Texas. It’s not that odd since it also is native to the region.
Lantana is loved by butterflies and nectar gathering insects, and just that is a valued argument for planting it in the garden. In well assorted garden centers you also get types that are sterile to avoid the poisonous berries.
Lantana loves heat and sun, so from December to March it looks just as scruffy as it radiates and glows all the summer season. But wait until the end of February, beginning of March with pruning, since the old branches and leaves protects against wind and cold until spring arrives.
Lantana can take a lot of hard pruning which is a good thing since it is a rapid grower. It gets a tad long and lanky if you don’t restrict it some.
The rule is basically that after the last frost you can cut back your lantana as much as you want. It will bounce back. I also cut them back once or twice during the summer, but not as much as the spring pruning. In the summer I shorten the branches with about one third if needed. Only to keep the plants bushy and keep it from overwhelming neighbour plants.