Cleistocactus strausii
As a houseplant, the Silver Torch cactus is an easy to take care of so long as over-watering is avoided. To naturally simulate the porous effects of the sand in its native habitat, it's important to ensure that excess water will not pool in the soil, causing the roots to become water logged.
This plant’s native habitat does not have winter, but when temperatures drop to the low twenties, it can exhibit signs of tip frost. 
The Silver Torch cactus is most susceptible to 
mealybugs 
and spider mite.
St. Johns River
Wetlands in the upper and middle basin are fed by rainwater, trapped by the structure of the surrounding land. It is an oxygen- and nutrient-poor environment; what grows usually does so in peat which is created by centuries of decaying plant material. Water levels fluctuate with the subtropical wet and dry seasons. Rain in central and north Florida occurs seasonally during summer and winter, but farther south rain in winter is rare. All plants in these basins must tolerate water fluctuation, both flooding and drought. Sweetbay ("Magnolia virginiana"), cypress ("Taxodium"), and swamp tupelo ("Nyssa biflora") trees often find great success in this region on raised land called hammocks. Trees that live in water for long periods usually have buttressed trunks, tangled, braided roots, or protrusions like cypress knees to obtain oxygen when under water, but the majority of plant life is aquatic. Wetland staples include the American white waterlily ("Nymphaea odorata"), pitcher plants, and Virginia iris ("Iris virginica"). In the southernmost points of the river, "Cladium", or sawgrass, grows in vast swaths of wet prairie that at one time extended into the Everglades. These wetland flora are remarkably successful in filtering pollutants that otherwise find their way into the river.