There are dozens, if not scores of spotted aloe species ranging in size from inky dinky to quite large for an aloe. Spotted aloes come from everywhere aloes come from- Africa and Madagascar (technically also Africa) as well as a small section of Arabia (technically part of Asia, though still mostly stuck to the African continent) and some small islands off the coast, also technically Asia.
I organize the spotted aloes into several random groups. These groups are strictly my own invention and have absolutely no usefulness in the real world of taxonomy. Some are branching aloes, some are trunking aloes, most are stemless solitary or suckering aloes, some are smaller, plastic-like plants, some a miniature, some are speckled rather than spotted, some are barely spotted at all while others are strikingly so, etc. In this article I will concentrate on only the stemless plants of medium to large size (miniature aloes will be discussed elsewhere). Where the cut-off between small and medium exists is not clear, of course, so I have made it a random one with the smaller aloes being the ones that are as small or smaller than my hand.
Example of the first aloe group- the larger spotted Aloes (Aloe duckeri); the 'plastic' spotted Aloe representative in second photo (supposedly Aloe somaliensis); and Aloe dinteri, the Namibian Partridge Aloe is an example of the third group of Aloes to be discussed
Some aloes are only really spotted when young (Aloe ambigens, Aloe arenicola and Aloe capmanambatoensis)- I don't really consider any of these spotted aloes as mature plants rarely have any spots (all these are my spotted seedlings)
The larger spotted aloes contain a large group of plants that are amazingly diverse within each species while being amazingly similar across species lines. This of course makes telling them apart an extremely difficult task. I am not too embarrassed that I cannot tell many, if not most, apart, as many reputable growers and sellers of aloes obviously cannot, either, having sold me many plants as one species that have turned out to probably be another. If these supposed ‘experts' cannot tell them apart, how am I supposed to be able to?
the first photo is of an Aloe maculata, young in full sun; the second photo shows the exact same plant later on grown in shade just to demonstrate how different the same plant can look in different circumstances... and then the third photo is of an Aloe grandidentata, which to me looks exactly like the Aloe maculata in the first photo... yikes!!
And as if that weren't confusing enough, here are three South African Aloes all considered spotted aloes, but without spots! The first is Aloe affinis, which sometimes has spots... and sometimes doesn't. Then Aloe immaculata is often included in the spotted aloe group as it looks exactly like them... but without spots (ever)... and lastly, this is my young Aloe petrophila sans spots... maybe it will get them later? Maybe it's in too much shade? Maybe it's NOT Aloe petrophila (though it flowered this winter and the flowers matched perfectly)... augh!!!
Some of these aloes are spotted with well defined spots (either circular or oval, though usually the latter) while others have a mixture of spotting and lines or streaking. Some have distinctly shaped ‘H' spots. Most have sharp teeth along the leaf margins.
Aloes with distinct spotting (Aloes duckeri, longibracteata, maculata)
Aloes with less distinct spotting (Aloes greenii, vogstii and petrophila (maybe))
One of the curious similarities of these larger spotted aloes is the tendency for them to have dried up, necrotic leaf tips in times of drought. This is not a characteristic necessarily unique to spotted aloes, but the spotted species seem to have exaggerated symptoms of leaf tip necrosis relative to most non-spotted species.
Aloes duckeri, greatheadii and parvibracteata all in times of scant rainfall (or lack of watering on my part) showing the dried, shriveled leaf tips
Another ‘regularity' is the similarity in their flowers, with most having highly branching flowers of pale pink to red-orange, either in open conical rosettes or somewhat open, head-shaped rosettes. Most flower in winter, but then most all aloes flower in winter. Some are summer or fall flowerers, though.
Aloe greatheadii, parvibracteata and zebrina showing all basically the same flower shape (the Aloe zebrina normally has pink-red flowers, but this is an usual color form... making identification even trickier sometimes)
This is the other basic flowering plan for the larger spotte aloes (Aloe maculata, Aloe unknown and Aloe umfoloziensis)
As a rule (probably not a hard and fast one) the larger spotted aloes seem to be pretty cold hardy, at least relative to a lot of other aloe species. Not a single one had much cold damage in my yard when it got down to 25F for over 7 hours... yet dozens of other aloes were badly damaged. These plants also seem to be quite tolerant of erratic watering practices, at least in terms of overwatering- have yet to rot one out by excessive watering, as I have done with a variety of other aloes. Without exception all these plants prefer full sun.
When young, many of these larger spotted aloes are striped and distichous (leaves in two planes only): Aloe brandraaiensis as a seedling, Aloe greatheadii as a dinky seedling, and a bit older (1 year older)
I am assuming all these similarities are not accidental and that most spotted aloe species are closely related.
The following are some of these larger spotted aloes. Note that almost all are from South Africa.
Aloe affinis (a spotted one)- South Africa; Aloe brandraaiensis, showing it's unsually large number of flowers typical for this species (also S Africa)
Aloe burgersfortensis Aloe duckeri (from Tanzania) Aloe dyeri
Aloe fosteri in flower (one of the nicest flowers of these spotted Aloes) and my own plant in second photo; Aloe gariepensis
Aloe esculenta from Angola Aloe dorotheaes from Tanzania
Aloe fosteri seedling, and adult in middle photo; Aloe greenii- both from South Africa
Aloe greatheadii Aloe greatheadii (aka Aloe mutans- this species has many synonyms) Aloe laterita
Aloe macrocarpa (aka Aloe commutata)- S Africa Aloe macrosiphon in flower, and close up- from Tanzania
Aloe maculata (aka Aloe saponeria) red flower and yellow flower form- this is the classic and most common of the large spotted aloes- S Africa; Aloe mudenensis, also S Africa
Aloe microstigmas from South Africa Aloe longibracteata (sometimes clumped with Aloe greatheadii)- also S Africa
Aloe prinslooi (and flower showing unique color in second photo; Aloe pruinosa- both from South Africa
Aloe pubescens- South Africa Aloe sinkatana and flower- sometimes considered a small spotted aloe- from Sudan
Aloe swynnertonii and flower- South Africa Aloe turkanensis from Kenya
Aloe vogstii Aloe zebrina Aloe umfoloziensis- all from South Africa
So, could you tell them all apart? I sure can't
The next group included in this article are the shiny, plastic-like Aloes, another group of very similar plants. All these plants are either from Somalia, Ethiopa or Mozambique. Some of these species are no more easy to tell apart from the above ones, and there is some heated disagreement as to what is what. These are in general, slightly to moderately smaller than most of the above aloes, but that is only a generalization. Unlike most of the above aloes, whose leaves have some flexibility, these aloes have completely inflexible leaves and bending them will result in broken leaves. The surfaces of these plants are shiny and smooth and have the texture of plastic. These aloes also have very sharp teeth.
The beauty of this group is Aloe harlana (Ethiopia), a solitary species that is larger than the others and has unique, dark orange head-shaped flowers; third photo shows a plant I bought as Aloe harlana- which it is NOT
Though it's a beautiful plant, this is Aloe hemmingii (from Somalia), perhaps the only spotted aloe more commonly sold than Aloe maculata, and ALSO sold as Aloe harlana and Aloe somaliensis
Aloe somaliensis (the real thing); next two photos show what is supposed to be Aloe somaliensis (from a reputable grower)- but if you see the typical Aloe hemmingii flower in the third photo, you can see this is NOT Aloe somaliensis
This MAY be Aloe mcloughlinii (Somalia)- though this species does have very similar species to A hemmingii; second photo shows my own crazy collection of N African 'plastic' spotted Aloes: from top left in clockwise fashion- Aloe harlana, Aloe hemmingii, Aloe mcloughlinii and Aloe somaliensis. The Aloe harlana and Aloe somaliensis sadly turned out to be (after flowering I discovered), as I suspected, Aloe hemmingii... sigh.
This very closely related Aloe, also from Somalia, is Aloe peckii, which, as a seedling, looks EXACTLY like all these other ones... but as it matures, it loses its spots (see second photo)... so this really isn't a spotted aloe... ?
Though perhaps related, this last plastic-like Aloe is Aloe suffulta from Mozambique and has long, skinny leaves (and super long, draping inflorescecnes with the flowers spread out by several inches- not terribly ornamental)... whew... at least one I can tell apart!
I do not know how cold hardy this group of aloes is, though most mine were undamaged by freeze down to 25F. However they are more prone to rot from overhead watering than are the larger spotted aloes. Some of these plants are quite tolerant of some shade, though none like full shade or dark environments. All tend to turn brownish in full, hot sun.
A much smaller group of aloes include the ‘wedge-leaf' or ‘Partridge' species- these are aloes with very thick, relatively short leaves with a distinct ‘V' in cross section. All three of these are from Southern Africa, though only one is from South Africa. Two have common names that include Partridge Aloe. These plants are only somewhat cold tolerant and mine were mildly damaged by the freeze. I have also succeeded in rotting several of these Aloes with overhead watering in both mid winter and mid summer. They appear to be very drought tolerant plants.
Aloe variegata is a common and beautiful spotted aloe from South Africa (common name Partridge Aloe); Aloe dinteri, in the next two photos, is from Namibia and called the Namibian Partridge Aloe
Aloe sladeniana is also from Namibia, and has no common name I am aware of... looks a lot like Aloe dinteri, but leaves are not arching as much
This last group of spotted aloes include a variety of species I was not able to group together easily.
More spotted aloe species that are either smaller, or are somewhat shrubby: Aloe amutadensis; Aloe ellenbeckii (personally, the two look identical, even in flowers... another confounding pair!); and Aloe andongensis which grows up several feet tall and branches
Three South African species that are either a tad small to be included above (Aloe aristata) or just barely have any spots at all (Aloe breviscapa and Aloe buhrii)
Aloe camperi 'Cornuta' is a monster species with a bit of trunk; Aloe deltoideodonta (Madagascar) is a smaller species and one of three forms is spotted; Aloe nobilis is technically spotted, though the spots are mostly colored, blunt thorns
Two mystery plants... this one is too small to be Aloe hemmingii, but too large to be Aloe jucunda (see later article on dwarf Aloes); Aloe that looks vaguely like the South African spotted species... but doesn't fit any... maybe some hybrid?
There, now I feel better... not a very organized or terribly informative article... but a decent INTRODUCTION to the mess that are the spotted Aloes. They really are wonderful landscape aloes... just don't get hung up on trying to tell them apart!