![]() |
|||
Nursery Hours: |
Phone:
(619) 291-4605 |
Delivery is available! |
All major credit cards accepted |
|
ENCEPHALARTOS HORRIDUS
Cycads come from many different regions of the world. As a group, they are very primitive plants that haven't evolved my since the time of the dinosaurs. Some are definitely dwarf in size while others get quite large. Leaf color ranges from green to blue, some with emerging new red colored leaves. Of all the cycads in existence, the ones with a blue color to the leaves are most popular. True, the common Sago Palm is more frequently seen in landscapes, but among collectors, botanists and cycad enthusiasts, the blues rank as number one. Encephalartos horridus is such a blue cycad and is native to the Eastern Cape region of the Republic of South Africa. Overall it is small in stature, likes sun and heat, and is fairly cold tolerant. From a nurseryman's point of view, I would rank it as the most popular of all the blue cycads. Almost all serious cycad enthusiasts have one or more in their collections or gardens. It has very spiny leaflets and develops a silver-blue color when in the sun. It also makes an ideal potted plant for a sunny location. Below I will discuss this species, its characteristics, its culture and usage in the landscape. |
![]() Encephalartos horridus, domestic plant |
![]() Encephalartos horridus, domestic plant |
![]() Encephalartos horridus, domestic plant |
When one researches the derivation of the word "horridus", such terms as "bristle", "shutter", "shrink from" are found. I think this all translates into the extremely prickly nature of the leaves and leaflets of this species. Leaves emerge from the trunk, go upright and then, to a greater or lesser extent, curve downwards toward the ground. Their length on mature specimens is usually two to three feet. Dwarf forms can have shorter leaves. The numbers of leaves vary with growing conditions but can be upwards of 20 or more. Leaf width is about 6 inches. As new leaves emerge, older leaves "lay down" closer to the ground. There is a short bare petiole proximal to the inner leaflets. The leaflets contained in the middle of a mature leaf
on most forms are approximately three to five inches long and one to one and a
half inches wide. The most prominent characteristics are the barbs or
lobes. These are one to one and a half inches long. There are two to
three of these lobes present. What distinguishes this species from similar
species is that that one or more of these barbs are oriented in a different
plant than the rest of the leaflets. They flip back in orientation.
Also, they also can overlap. This
accentuates the prickly nature to the leaf. The barbs also have a very
sharp spine at the terminal point. This "flip" of the lobes is much less
apparent or nonexistent in the similar species E. trispinosus.
Proximal leaflets are reduced in size compared to leaflets farther out on the
leaf in the mid-leaf area. Below are photos of leaves and leaflets to give
you an idea of their appearance. As you look at them, look for the change
in the orientation of the pointed lobes. |
![]() Encephalartos horridus, leaf of nursery plant |
Encephalartos horridus leaves, note leaflet lobes |
Encephalartos horridus, leaf |
![]() E. horridus, close up of leaflets showing flip on the lobes |
![]() Nice demonstration of the overlapping & barbed leaflets |
Another example of same. |
Botanists will often interchange the words "stem", "caudex" and "trunk" when referring to the woody structure below the crown of leaves. Compared to other species in this genus, I would say that the average stem of an E. horridus is small to medium in size. Portions of the stem can be subterranean and not seen. Above the ground, stem height can reach over time up to three feet, rarely a bit taller. Such a plant is extremely old. Diameter is small to medium in size, usually about eight to ten inches with some being even thicker. Trunks usually do not branch as seen with other species but may have an ample number of offsets or "pups" at the base. This varies from plant to plant with some making many offsets and others few or none at all. The trunks tend to be a light tan in color and may have some wooly material at the distal apex. The appearance of a mature trunk is woody. Old stubs of leaf bases may remain near the top of the stem. As a young plant is grown, it produces a circular trunk that is near round in shape. Over time, this "ball" will increase in diameter until it reaches a mature width. At that point it will begin to put on vertical height, maintaining the diameter it had attained. In other words, the trunk expands laterally before it puts on much vertical height. It is possible, especially with containerized plants, for a specimen to begin vertical growth before the stem has reached a typical mature diameter. This would give a thinner trunked specimen. I have seen this with many blue Encephalartos. It is also possible to stunt the size and height of this species by growing it in a small container, thus creating a "bonsai" specimen. Also be aware that dwarf forms of this species do have smaller stems naturally. |
![]() Encephalartos horridus, very old plant showing trunk |
![]() E. horridus, nursery plant with 10" round caudex |
Very old plant with approx. 2 feet vertical height |
An average size for the crown of leaves of E. horridus would probably be about a three foot diameter. However, this varies from plant to plant. I have seen specimens where the diameter is six feet and as small as eighteen inches. Also, some plants have very re-curved leaves, where the ends of the leaves curl downwards, sometimes almost forming a 360 degree circle. Others are very gently flexed downward making the crown width greater. A plant grown in less than full sun may "stretch" its leaves out and expand the crown. Plants grown in very bright sun tend to be more compact. There is also the topic of two different forms or varieties of this species: the typical form and the "dwarf" form, with smaller leaves and stem. Most agree that there is a dwarf form of this species. But, it is not as simple as saying "there's the little one and the large one". I've been growing this species for over thirty years and can comment that, when one looks long enough, its almost like looking at children. All are similar, but very few have the exact same appearance. I had a friend who specifically collected only blue cycads. He had accumulated well over thirty plants of this species and grew them all to maturity. No two looked identical. This variation in the size, shape and appearance of Encephalartos horridus is part of the charm of this species and most likely is a principal that can be applied to cycads in general: There is variation, plant to plant. From a consumer point of view, it does mean that, when buying a plant, you pick out one you really like. Don't assume all are the same. Examples of crowns of leaves of E. horridus are given below. As you look at them, you'll begin to appreciate their spiny nature and the characteristics of the leaves and crown. |
Encephalartos horridus, smaller domestic plant |
![]() A very nice nursery specimen in a box |
![]() Encephalartos horridus, domestic plant |
![]() Encephalartos horridus, domestic plant |
Nursery plant with a very silver color to leaves |
![]() Encephalartos horridus, domestic plant |
Like other Encephalartos, E. horridus reproduces by
forming a strobilus or "cone". These are reproductive structures that
emerge out of the apex of the stem. There can be one or several. All
cycads are deioceous. This means that you have either a male or a female
plant. Cones appearance and structure is one of the main means of
identifying species. Pollen from the male must be introduced into a
receptive female to produce
viable seeds. Realizing that taxonomists can identify species by looking
at their cones (in addition to other morphological traits), it is not surprising
to find that cones on different species appear unique to that species. In
general and to make a simplification, male cones tend to be more tubular and thin.
Female cones are thicker and, according to some, look like a "pineapple".
The males look more like a corn cob. Pollination in habitat is typically accomplished by insects or beetles. Wind dispersion or manual transmission by humans can also result in viable seeds. But, without a male producing pollen and a receptive female, no viable seeds can result. The female cone of E. horridus is usually a single cone about ten to sixteen inches long and blue-green in color, often with tan or brown between or over the scales. The male cones, typically one or two present, are of similar size to the female but thinner and tapered at both ends. The color is similar. With pollination, the female cone will expand in size over time. The last two pictures show female cones. Cone life is typically three to six months; female cones that have been pollinated stay present on the plant a much longer time while the seeds mature. |
![]() Encephalartos horridus, cone, uncertain sex |
![]() Encephalartos horridus, female cone emerging |
Encephalartos horridus, female cone |
Encephalartos horridus (along with E. trispinosus, lehmannii and princeps) is described as a "blue" cycad. In fact, this term "blue" is often used to describe many species of plants including popular palms like Bismarckia nobilis and Brahea armata. But, I must clarify here that we are not talking about a dark blue like one would see in the ocean. Rather, it is a "silver-blue". I like to think of it as looking up at the blue sky above on a minimally foggy day. So, if you were to refer to the color of this species as 'silver", you would not be wrong. You will see variations of this among representatives of this species varying from a definite blue green to a darker blue to a light silver and sometimes almost to a silver white color. This color is present because of a waxy substance that the
leaflets produce on the leaflet surface. It is almost like a
fine powder. It is most apparent on newer leaves and persists on the
leaves over time. But, with time and the physical action of rain and
weather, can actually wash off of older leaves. Or, it can become less
intense and muted. The wax is actually washing away. It also wipes
off with the stroke of your finger. Another interesting thing about this
waxy substance is that a plant
grown in a very humid greenhouse may emerge quite blue, but over time convert to
almost a green color. This is very common to see. But, when you move
this green plant into the bright sun, this green color will gradually become
more blue, especially on the newer leaves grown outdoors. The same can be
seen with a plant grown in the shade; it may be less blue. |
![]() This E. horridus is a silver blue color |
![]() This specimen is more of a blue color |
![]() This plant also has a blue-green color |
This greenhouse plant has green leaves |
A gorgeous blue color here |
![]() Here's a classic silver colored E. horridus |
There is nothing quite as exciting as seeing a specimen of E. horridus that throws new leaves. Such throws of leaves, in a good size plant, emerge together, often as many as twenty leaves at one time. As mentioned above, new leaves usually show their full complement of blue waxy color. I've often felt that this is a pro-survival mechanism for the plant. It is prepared for hot and dry conditions and produces plenty of protection for the new leaves. This guarantees survival of the newest and most important leaves. Another interesting thing about a new throw of leaves on this species is that often they emerge an almost purple, dark color. And, as the leaves emerge and develop, they will turn and pinkish-brown and finally show the typical blue. The series of four photos below demonstrates this sequence. Note how the last photo shows the more typical, expected blue color. This is from an offset that was rooted out in pumice. I've also shown a series of two photos of a very old E. horridus dwarf to demonstrate the color of newly emerging leaves. |
![]() Photo 1 of 4, emerging leaves rooted offset |
![]() Photo 2 of 4, emerging leaves rooted offset |
![]() Photo 3 of 4, emerging leaves rooted offset |
![]() Photo 4 of 4, finally showing change to blue leaves |
Another E. horridus, new flush of leaves |
Another E. horridus, new flush of leaves, close up |
Sometimes newly emerging leaves can demonstrate a problem with the plant. The picture below shows some very yellow newly emerging Encephalartos horridus leaves. I do not feel that these are entirely normal and am suspicious of a nutritional deficiency, many times with lack of microelements. When I see this it concerns me and I will treat with fertilizer. Note how it is different than the brown or purple seen above. |
A yellow new flush, perhaps from nutritional problems |
OFFSETS OR SUCKERS OF ENCEPHALARTOS HORRIDUSLike many other types of cycads, Encephalartos horridus can grow pups or offsets at the base of the primary trunk. This is a form of natural propagation by the species. Remember, the plant reproduces by the formation of seeds. Offsets or pups are a form of propagation of the species but a vegetative type not requiring a nearby plant of the opposite sex. With offsets, the sex of the offspring is always the same sex as the parent plant. In other words, if you have a female, a removed offset will also be a female. For those wanting to establish a reproductive colony of a species, getting a rooted out offset is a way to speed up the establishment of a breeding colony. If you need a female, you can get one by getting an offset of a parent female. Offsets begin as a small adventitious bud growing off of the base of the mother trunk. These are often subterranean and might not initially be seen. They are supported nutritionally by the mother plant until they are removed from the main trunk. However, over time, they do produce their own roots and can be physically removed and grown as a separate plant. Within a year or two, such suckers will form their own leaves. When such suckers are removed, there is a technique for establishing them and giving them the best chance to survive. Below I will discuss how to do this. A parent plant has the ability to produce a large number of offsets or suckers. It is peculiar that some parent plants have a propensity for produces offsets. And, others may never produce even one. Also, some species are more inclined than others to make offsets. E. horridus is known for producing good offsets. When basal offsets are removed from the parent plant, typically within a few years that same plant will produce more suckers. And, these likewise can be removed. Below are some pictures of plants with pups at the base. I will show a few close up pictures to demonstrate the suckers. Note how the suckers are making their own leaves. The third picture shows how you see leaves adjacent to the parent plant, but you cannot actually see the stem of the pup. It is subterranean in this case. Like many other types of cycads, Encephalartos horridus can grow pups or offsets at the base of the primary trunk. This is a form of natural propagation by the species. Remember, the plant reproduces by the formation of seeds. Offsets or pups are a form of propagation of the species but a vegetative type not requiring a nearby plant of the opposite sex. With offsets, the sex of the offspring is always the same sex as the parent plant. In other words, if you have a female, a removed offset will also be a female. For those wanting to establish a reproductive colony of a species, getting a rooted out offset is a way to speed up the establishment of a breeding colony. If you need a female, you can get one by getting an offset of a parent female. Offsets begin as a small adventitious bud growing off of the base of the mother trunk. These are often subterranean and might not initially be seen. They are supported nutritionally by the mother plant until they are removed from the main trunk. However, over time, they do produce their own roots and can be physically removed and grown as a separate plant. Within a year or two, such suckers will form their own leaves. When such suckers are removed, there is a technique for establishing them and giving them the best chance to survive. Below I will discuss how to do this. A parent plant has the ability to produce a large number of offsets or suckers. It is peculiar that some parent plants have a propensity for produces offsets. And, others may never produce even one. Also, some species are more inclined than others to make offsets. E. horridus is known for producing good offsets. When basal offsets are removed from the parent plant, typically within a few years that same plant will produce more suckers. And, these likewise can be removed. Below are some pictures of plants with pups at the base. I will show a few close up pictures to demonstrate the suckers. Note how the suckers are making their own leaves. The third picture shows how you see leaves adjacent to the parent plant, but you cannot actually see the stem of the pup. It is subterranean in this case. |
![]() Note multiple suckers at base of this plant |
Nursery plant developing offsets |
![]() Close up showing offset from an 8 inch parent |
CULTURE AND GROWTH OF ENCEPHALARTOS HORRIDUSSoil: Like many other types of
cycads, E. horridus like a good draining soil. What this means is
that the water given to the plant needs to pass through the growing medium
fairly quickly. If you are making your own potting mix, this can be
accomplished by adding coarse sand, pumice, scoria, good caliper decomposed
granite, very fine rocks, or other coarse material. Things such as fine
leaf mold, very fine sand, clay-like topsoil or decomposed organic materials
tend to slow the passage of water and retain moisture. With a good mix,
when you water a containerized plant, you should see water trickling out the
bottom of the pot in a matter of seconds. We give a good formulae for
cycad soil elsewhere at this website. Of note, we also use horticultural
charcoal routinely in our cycad mix. Shown below are a picture of pumice,
coarse #12 grit sand, and a photo one of our cycad soils. Over the years I
have experimented with a variety of soils for cycads. I have found that
many different types of soil or mixes will work fine as long as they have good
drainage. In other words, no single mix "is the best".
|
![]() Pumice, great for drainage |
![]() #12 coarse sand promotes drainage |
![]() One of our cycad mixes; note charcoal |
In terms of the best soil type in the garden, the same principals apply. E. horridus likes good drainage. You can actually dig a hole in the garden and fill it with water. You'd prefer that this water disappears in a matter of an hour or two. If it persists for more than 24 hours, you're going to have problems growing this species unless you change things. Adequate creation of a good draining garden is beyond the subject at hand, but sometimes adding the additives above will help if you have drainage problems. Also consider raised growing beds or "mounding" up the soil to produce a small hill and planting your cycad on top of this hill. Growers in such rainy climates as seen in Florida or Hawaii often do this. This allows the plant to spread out roots above the wet lower water table area. Sun: In general, Encephalartos horridus, in general, prefer full bright sun and heat. This is especially true along the coast where full sun is almost mandatory. However, in far inland areas or desert climates, it may be necessary to give this species less than full sun. In desert areas like Phoenix, Arizona or Las Vegas, Nevada a few hours of sun may be as much as this species can tolerate. Knowing that your plant wants sun, you must remember to acclimate a purchased plant to your sun. Plants grown under shade cloth or in a greenhouse are not used to outdoor sun. In the greenhouse, their color may be green more than blue and they are seeing more humidity than they'll experience outdoors. But, they will convert to blue in the sun. One should slowly acclimate a greenhouse grown plant into the sun over time. If you a growing this species as a houseplant, it would be advisable to put the plant directly in front of a bright sunny window. If grown inside a greenhouse, put the plant in a hot and bright area of the greenhouse. If you are trying to grow this species in a tropical area where you have long monsoonal seasons, consider putting the plant under a overhand or eave of the house where sun hits the plant but the rain doesn't reach it. Or, if an open rainy area, make sure you're giving the plant good drainage. Water: This species of cycad doesn't need or want a lot of water. One could almost consider it xerophytic because it can go a week or two between waterings. Too much water and continual damp soil are an enemy of not only this species but also of many cycads. In most gardens in warm climates, watering plants twice a week is adequate. During the winter you may not have to water the garden for a month if you get adequate rain. At our nursery, we water containerized cycads ever week to ten days. During hotter summer periods we may water twice a week. It is probably better to give less frequent deep watering as opposed to frequent shallow watering. You can evaluate your watering by checking the top inch or two of the medium. You should allow this superficial soil to dry out before giving more water. I like to tell clients at the nursery that under-watering rarely gets these plants in trouble. Over-watering can kill them quickly. Fertilizer: Similar to palms, cycads like an N:P:K ratio of approximately 3:1:3 or 3:1:2. This would translate into an actual fertilizer with a ratio of 15:5:15 or 12:4:8. For the garden, we prefer slow release preparations that are time-released over a given period. Most slow release fertilizers are either 90, 180 or even 360 day formulas. Follow the directions. Also, get a fertilizer that has microelements such as magnesium, iron, etc. When applying fertilizer, spread it onto the surface of the soil below all the leaves. Do not throw it directly into the crown of the plant and try to stay about six inches away from the stem. You can rake the fertilizer into the soil if you wish. Below are pictures of fertilizer preparations. the second photo shows a soluble fertilizer like we use inside our greenhouses. I show it so you can see a list of container microelements. |
![]() |
![]() |
Pests:
|
A new E. horridus one leaf seedling |
E. horridus, 5 gallon plant |
![]() E. horridus, 15g plant with offsets |
If you have purchased an offset of this species or removed one
from a mature plant, this can be successfully rooted out and grown. It
actually is not that difficult. Try to be gentle in handling the offset.
Inspect it for rot. This will usually appear as a soft area or discolored
brown area. If your offset has a large root attached, remember to inspect
it as well. Often these large primary roots get damaged or bruised and
this leads to rot. Any neglected rot can travel up the root and kill the caudex. Any rotting areas must be surgically dissected away and treated with fungicide
and sealers. After inspection we recommend soaking the entire offset in a fungicide
solution for several hours. Then, while wearing gloves, apply a root stimulant and a powdered
fungicide to the bottom of the caudex. If you dissected any root, also
apply it to the cut surface of the root. Place the caudex
into a very good draining mix such as pure pumice or possibly coarse sand.
The lower portion of the caudex, perhaps 30% up to 50% should be below the
surface of the rooting medium. We are not a proponent of planting the
entire caudex into the soil (up to the apex of the offset). Water the
plant about once a week by watering the pumice (or other medium) and not the top
of the caudex. The latter can lead to rot. Rooting typically takes
about six to twelve months. Bottom heat is not necessary but place the
rooting caudex into a warm area. While
waiting for roots, grow the plant in filtered light or inside a greenhouse.
Don't be afraid to fertilize lightly from time to time. You would prefer
to see roots forming before you get a throw of leaves. Sometimes caudexes
that throw leaves first before rooting will later go into decline and die.
Once the offset is rooted out substantially, it can be repotted into a larger container utilizing regular cycad mix. It is fine if it has roots and no leaves. The leaves will appear later. Don't overwater it. As time goes by, slowly acclimate it into bright light or full sun. Anticipate that it will stay in this new container for at least 2 to 3 years. The first picture below shows an offset that has been put into pure pumice for rooting. The second photo shows a plant that, after approximately 18 months, has thrown a set of leaves. Be aware that this first set of leaves may not be a full complement of leaves. Do not worry about this. Future swirls of leaves will show a greater number. |
A good sized offset in pure pumice |
A rooted out offset that has thrown leaves |
When removing a pup on E. horridus, the size should be at least three or four inches diameter. Very small pups don't do well and your losses will be much greater. As mentioned above, it can take up to twelve months to get a good set of leaves when rooting out a caudex. Don't be overly aggressive, "always checking for roots", or you will break off new roots. These newly forming roots are very fragile. Once they are three to four inches, it is probably ok to repot the offset. However, waiting for more mature and extensive roots is probably best. Some nurserymen will try to sell an offset when it has a minimal set of roots, for example a few roots down an inch or two. We don't like doing this and prefer to market plants only when they have an excellent system of roots. The photos below show you an offset that we rooted out. Notice the great set of roots shown. |
Photo 1 of 3, rooted offset E. horridus |
Photo 2 of 3, rooted offset E. horridus |
![]() Photo 3 of 3, rooted offset E. horridus |
USAGE OF ENCEPHALARTOS HORRIDUS IN THE LANDSCAPEEncephalartos horridus is a great addition to almost any garden where weather permits it to thrive. When selecting a location to grow one, do not put it too close to a pathway as the leaves are very prickly. But, don't put it so far back in the garden that you cannot see it. As this is a relatively small cycad, it should be no more than six to eight feet from a vantage point to properly see and enjoy the plant. If it's placed behind other plants or behind larger cycad species, it would not be visible. Also plant it in an area of full sun if you are along the coast. Guarantee that you've selected a location where adjacent plants won't, over time, shade out your horridus. Some like to plant E. horridus in colonies for future seed production. Others like to have a "blue area" of the garden and put horridus with similar blue species like lehmannii and trispinosus. However you plan to do it, you'll really enjoy having this blue cycad in the garden. |
Coning size E. horridus in the garden |
Multiple cycads in a garden |
E. horridus in cone in a garden |
Encephalartos horridus is a very rare and desirable blue cycad that does well in Southern California and many areas around the world. It is small to medium in size and never gets over about six feet tall. It is a very prickly plant with pronounced barbs on the sides of its leaflets. It has blue leaves which are the result of a protective wax produced by the leaves. In hot desert areas it is best to give it some protection from full sun. This species likes soil with good drainage and doesn't like to be over-watered. It is easy to grow if given the correct growing conditions. Like all cycads, this species produces reproductive cones. There are both male and female plants and pollen must be transferred to the female cone to make fertile seeds. The species is propagated by seeds from the cones or from vegetative means by rooting out naturally occurring offsets from the base of a parent plant. When grown in the garden, proper selection of location is important so people walking by don't brush up against the prickly leaves and so the plant always gets adequate sun. Among enthusiasts, this is one of the most sought out of all cycads and is always hard to find and usually expensive to buy.
Thank you for reading this article. Feedback always appreciated. Check elsewhere at this site for over 4000 photographs and 50 articles on palms and cycads. Phil Bergman Owner Jungle Music Palms and Cycads Nursery: 450 Ocean View Ave, Encinitas, CA 92924 Phone: 619 291 4605 Email: phil.bergman@junglemusic.net
|
TO SEE ARTICLES ON ALL THE ENCEPHALARTOS SPECIES, CLICK HERE |
![]() |
TO READ MORE GENERAL ARTICLES ON CYCADS, CLICK HERE
Mini Site Directory: |
|||||||||
![]() |
|