The aloe is a genus of about 300 species of rosetted, evergreen perennials that come from southern Africa, Madagascar and the Arabian Peninsula. Most have succulent leaves whose racemes are cylindrical or three angled.
The author of a book on cactus and succulents as house plants says of the aloe, "Rather dull plants." Hardly.
The aloe is a member of the lily family but looks more like a member of the agave (Century Plant). It is a succulent which grows low along the ground, as a shrub, or as a tall plant.
The flower, which grows on a stem from beside the rosette of leaves (like the Century Plant), can be red, orange, or yellow.
Where temperatures get below 50 degrees they should be grown indoors as a houseplant. In warmer climates they can be grown in a desert garden. Aloes are excellent in a container garden.
Soil, Water, and Light
They grow best in potting soil with sand or perlite mixed in. A cactus potting mix is perfect.
Generally the plants like bright light. However, some do not like full sunlight, especially in southern climates - the leaves tend to burn and turn brown. Some, however, love direct sunlight.
Do not water these plants too much, perhaps once a month and even less in the dormant period of the winter. These plants can be over watered easily but rarely succumb to lack of water.
The plant pictured here is Aloe arborescens also known as the Candelabra Plant, taking it's name from the appearance of the mature plant.
If you snap the leaf of an aloe vera (aka aloe barbadensis) you will reveal a juicy pulp which contains a thick fluid which is made into laxative and beauty aids. We still use it to rub on burns, and I have seen the leaves sold in the produce section of the grocery store.
You can propagate the aloe plant with cuttings (or pieces that fall off the main plant). Start with a sterilized knife and cut off a leaf. Once the cut is done let the leaf rest for a few days to callus the cut end. You can also dip in a hormone powder to prevent fungus. Then stick it back into potting soil mixture to re-root it. Water it after sticking it in the soil, but then very sparingly (or not at all) for a few weeks until the roots begin to form. It is susceptible to rotting at this point.
Black spots is usually a leaf fungus and you should move the plant to a brighter spot with drier air and water it less.
Reddish leaves usually are as a result of too much sun or too little water.