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Ferocious Blue Cycad
Encephalartos horridus

Family: Zamiaceae
Genus: Encephalartos (en-sef-uh-LAR-tos) (Info)
Species: horridus (HOR-id-us) (Info)
Synonym:Zamia horrida

Category:

Tropicals and Tender Perennials

Cycads

Height:

36-48 in. (90-120 cm)

Spacing:

4-6 ft. (1.2-1.8 m)

Hardiness:

USDA Zone 9a: to -6.6 C (20 F)

USDA Zone 9b: to -3.8 C (25 F)

USDA Zone 10a: to -1.1 C (30 F)

USDA Zone 10b: to 1.7 C (35 F)

USDA Zone 11: above 4.5 C (40 F)

Sun Exposure:

Full Sun

Danger:

Seed is poisonous if ingested

All parts of plant are poisonous if ingested

Plant has spines or sharp edges; use extreme caution when handling

Bloom Color:

Inconspicuous/none

Bloom Time:

N/A

Foliage:

Grown for foliage

Evergreen

Silver/Gray

Other details:

Drought-tolerant; suitable for xeriscaping

This plant may be considered a protected species; check before digging or gathering seeds

Soil pH requirements:

6.1 to 6.5 (mildly acidic)

6.6 to 7.5 (neutral)

Patent Information:

Non-patented

Propagation Methods:

By dividing rhizomes, tubers, corms or bulbs (including offsets)

From seed; germinate in vitro in gelatin, agar or other medium

Seed Collecting:

Unknown - Tell us

Regional

This plant has been said to grow in the following regions:

Mesa, Arizona

Phoenix, Arizona

Carlsbad, California

El Cerrito, California

Encinitas, California

Hayward, California

Reseda, California

Spring Valley, California

Thousand Oaks, California

Tulare, California

Visalia, California

Naples, Florida

show all

Gardeners' Notes:

3
positives
2
neutrals
0
negatives
RatingContent
Positive

On Sep 29, 2013, palmbob from Acton, CA (Zone 8b) wrote:

Many confuse this species with Encephalartos trispinosus or Encephalartos arenarius blue, both very similar plants. Of the three, this one tends to be the smallest over all, and usually much less robust than E arenarius. Leaves of all three tend to be pale bluish and have multiple spines. But E horridus leaves have a 90 degree twist to them the other two do not tend to have. E arenarius leaves are much wider and have a lot more surface area than the other two, and the blue forms are quite blue, while E horridus tends to be much whiter to pale blue-green (greenish in humid climates). E trispinosus leaves do not have the twist, and usually have three spines (as opposed to 4 of horrid us), but there are so many variations of each species, this is not always a good characteristic to use. ... read more

Positive

On Oct 23, 2012, Lightray from Carlsbad, CA (Zone 10a) wrote:

The attractive blue color is a nice addition to the garden. One of the easier to grow of the blue cycads if it gets sufficient sun and good draining soil. I get good blue color even within half a mile of the beach in North San Diego County, where we often see May Gray and June Gloom to start the summer.

Positive

On Oct 30, 2011, BayAreaTropics from Hayward, CA wrote:

This is a sun worshipping plant. If you dont have a spot that gets near sun up to sundown light,it will not do well. I have a plant that looks to be a seedling but is already four years old+ with a stubby (and now exposed by accident due to its pot being knocked over) caudex that is trying to push out a single frond. It's a long story of trial and many errors with an expensive,delicate plant.
But-think of it as a light needy cacti and you are much closer to having them do well,then thinking of it as a Sago or wet climate cycad.

Neutral

On Jun 21, 2007, Cretaceous from El Sobrante, CA (Zone 9b) wrote:

Encephalartos horridus is native to Cape Province, South Africa.

It grows in dry, desert-like scrub and bush habitat, where annual rainfall is 10-24 inches.

Encephalartos are listed on CITES Appendix I.

Neutral

On May 29, 2001, BotanyBob from Thousand Oaks, CA wrote:

This plant belongs to the Gymnosperms (cone-forming plants) though it's really not very closely related to most other Gymnosperms like pines. It looks a lot more like a palm than anything else. Typical to most other cycads, this plant has a short, succulent trunk full of starch, which is the 'life's blood' of the plant. The roots can be hacked off, as can the leaves and cones, and as long as the trunk, or caudex as it's called, is intact, it will usually recover. This characteristic makes this plant relatively easy to transplant.

Originally from Southern Africa, E horridus is a very spiny and interesting plant, having bizarrely twisted leaves that erupt out of the top of the caudex (sort of palm-like) and incredibly spiny, stiff, blue leaflets (hence the 'ferocious' name... read more