GENLISEA - Cultivating Carnivorous Plants (2015)

Cultivating Carnivorous Plants (2015)

GENLISEA

Genlisea violacea plant showing both the white underground traps

and the green, aboveground photosynthetic “leaves.”21

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CULTIVATING CARNIVOROUS PLANTS

The genus Genlisea, commonly known as “Corkscrew

Plants,” consists of 31 species of small, rosetted plants

native to South America and Africa. Despite being

identified as possibly carnivorous by Charles Darwin,

they were not proved to be carnivorous until 1998.

Two species, Genlisea margaretae and Genlisea aurea, have

the smallest known genomes of all flowering plants.

Genlisea have two types of leaves: the small,

green, roundish, photosynthetic leaves that grow in a

small rosette, and the white, subterranean, carnivorous

leaves that give the genus its common name. The

carnivorous leaves begin as long tubes that branch at

hollow, bulb-like growths called “utricles.” Below

these utricles, the tubes split into two branches. Each

branch consists of a furrowed spiral, with the furrows

having hairs pointing towards the utricle. A small

opening allows prey creatures to enter the trap itself,

after traveling along the furrows.

As with Utricularia, Genlisea do not have roots.

Instead, the white carnivorous leaves serve to anchor

the plant to their growing medium. In some

conditions, these can also float freely in water,

catching a different set of prey than is present in the

soil.

Genlisea aurea flowers.22

Most species of Genlisea have either purple or yellow flowers. Some are self-fertile, whereas others

require some stimulation to set seed. Perhaps most interesting among the genus is Genlisea glabra, which has

flowers remarkably similar to those of Utricularia amethystina. Both grow atop the Tepuis of South America, an

area with few pollinators. It is theorized that these two plants share the same pollinator.

In Cultivation

Many species of the genus Genlisea grow as annuals during

the wet season in cooler, montane areas. Most grow as small,

non-spreading rosettes. Therefore, the best way to propagate

them is either through leaf-pullings or via seed. Leaf-pullings

have a lower success rate than with Pinguicula, but they are

usually fairly successful if a bit of the whitish leaf base is still

attached to the photosynthetic leaf.

Genlisea are fairly unique among carnivorous plants as their

trapping mechanism makes them amenable to set-ups that

submerge the trapping mechanism but allow growers to view it.

The easiest way to create such a set-up is to pot the plant in a

small net pot and fit that pot over a jar or clear container, which

The light yellow flowers of

can be placed in an opaque container. Fill the jar with water.

Genlisea filiformis.23

Within a few months, the white carnivorous leaves will have

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NATCH GREYES

grown through the openings in

the net pot and into the water.

G. hispidula

Genlisea hispidula is among the

most commonly seen Genlisea in

cultivation. As with most species

of Genlisea, it is not as commonly

cultivated as it once was (during

the mid-2000s). Still, it is not an

uncommon plant in cultivation.

Like other Genlisea species,

Genlisea hispidula does well in

terrariums. Almost submerging

this species in water is best.

Submersion appears to trigger

flowering in some clones of

Genlisea hispidula.

Genlisea repens “leaves,” which are very similar to the

If placing Genlisea hispidula in

a terrarium is not possible, watch

“leaves” of every other member of the genus Genlisea.24

for signs of low-humidity stress.

In low-humidity conditions, it will produce fewer leaves and is unlikely to flower. Note, however, that

flowering does take a toll on this species, and naturally results in the loss of a fair number of green

photosynthetic leaves. The flowers of this species are self-fertile, and the tiny black seeds will spill from the

seed capsule as it unwinds after the seed has fully matured.

My standard growing guide for Genlisea follows:

Media: Live sphagnum or long-fiber sphagnum seems to work best, but they will tolerate a peat-

heavy peat-to-sand mix. I am not aware of anyone using ferricrete in cultivation.

Moisture: Most Genlisea grow in environments that are frequently flooded during the growing season.

As such, the water level should be kept high, and the pots should be flooded occasionally.

Humidity: Humidity should be high, as this genus is used to transitioning between flooding and

barely moist medium. Some species, such as Genlisea aurea, can produce a gelatin which covers their

leaves. This gelatin will not be produced when humidity is too low.

Pot Size: Genlisea is not particular about pot size. One popular method of growing the genus is to

suspend a net pot in a container full of water and shade the water container. That way, the traps will

grow through the holes in the net pot and into the water, allowing the grower to show them off.

Feeding: It is hard to tell whether a foliar fertilizer is beneficial as with terrestrial Utricularia because

Genlisea do not tend to spread except by seed.

Temperature: Genlisea seem to prefer temperatures in the 60° - 80° F (16° - 27° C) range, but they can

tolerate temperatures both lower and higher than that range.

Dormancy: Dormancy is not required for Genlisea. Several months after germination, annual species

will die after going to seed. Perennial species should be kept in the same conditions year round.

Propagation: Genlisea are best propagated via seed but can be propagated by leaf-pullings. Seed does

not require any kind of stratification. Leaf-pullings should be made to lay flat on the media and

covered with a pinch of media.

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CULTIVATING CARNIVOROUS PLANTS

The following table of all known Genlisea species includes their distribution and cultivation type in order

to facilitate thoughts on care:

Species

Distribution

Flower Color

Habitat

Dembos, ephemeral flush vegetation on slopes of

inselbergs, and in wet ferricrete soils at altitudes

africana

Africa

Purple

from 3,937 - 4,921 ft. (1,200 - 1,500 m).

angolensis

Africa

Purple

Ferricrete soils near rivers.

Sandstone highlands among grasses in water-logged

seepages, usually submerged, in black humus-rich

aurea var.

soil at altitudes from 1,804 - 8,366 ft. (550 - 2,550

minor

South America

Yellow

m).

Sandstone highlands among grasses in water-logged

seepages, usually submerged, in black humus-rich

soil at altitudes from 1,804 - 8,366 ft. (550 - 2,550

aurea var. aurea South America

Yellow

m).

Ephemeral flush vegetation of inselbergs of Guinea,

growing on the slopes only during the few weeks of

barthlottii

Africa

Purple

the wet season, when water floods the slopes.

Lithophyte near Fumaça waterfall at around an

exhibitionista

South America

Light Purple

altitude of 2,822 ft. (860 m).

South America,

Sandy, marshy highlands at altitudes of 3,937 - 4,757

filiformis

Cuba

Light Yellow

ft. (1,200 - 1,450 m).

Among grasses; often confused with G. violacea, but

flexuosa

South America

Purple

with twining inflorescences.

Light Purple to Inselbergs, where it grows with U. amethystina and

glabra

South America

Pink

has very similar flowers.

glandulosissima Africa

Tiny, Greenish Bogs with ferricrete soils.

guianensis

South America

Light Purple

Fixed-aquatic.

Wet swamps, bogs and seepage areas, ferricretes,

sphagnum cushions, and as an affixed aquatics in

Purple and

marshy streams from sea level to an altitude of

hispidula

Africa

White

8,858 ft. (2,700 m).

White with

lobata

South America

Purple

Cool, montane habitats.

Africa,

Nutrient poor wet areas on monadnocks

margaretae

Madagascar

Purple

(inselbergs), ferricretes, and swamps.

Noticeable metallic shine on the flowers, forming a

metallica

South America

Purple

corm to survive dry periods.

Lithophyte within the sprays of waterfalls and on

nebulicola

South America

Light Purple

rock surfaces.

Tepuis in swamps and southeast facing slopes at

nigrocaulis

South America

Yellow

around an altitude of 5,249 ft. (1,600 m).

In well-drained, sandy soil among tall grasses in

oligophylla

South America

Light Purple

areas that are only slightly moist in the dry season.

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NATCH GREYES

South America,

oxycentron

Trinidad

Yellow

Grassy, white sand savannas.

Yellow with

pallida

Africa

Purple

Permanently wet peat bogs.

pulchella

South America

Light Yellow

Moist sandy and gravelly places.

Wet, partly flooded sandy soils in a lake or swamp

areas and on sandstone rocks found at an altitude

pygmaea

South America

Yellow

from 2,953 - 4,593 ft. (900 - 1,400 m).

Affixed-aquatic in mountainous areas at an altitude

repens

South America

Yellow

from 1,640 - 3,937 ft. (500 - 1,200 m).

roraimensis

South America

Yellow

Tepuis alongside Heliamphora and other carnivores.

sanariapoana

South America

Light Purple

Wet areas among grasses.

stapfii

Africa

Purple

Wet, rocky areas among grasses.

White with

Ferricrete soils in wet depressions and marshes;

subglabra

Africa

Purple

associated with Cyperus.

White with

subvirdis

Africa

Purple Veining Among grasses.

Herbarium material from Moxico, Angola in

taylorii

Africa

Purple

ferricrete soils in wet depressions.

Campos Rupestres montane savanna of central and

eastern Brazil at an altitude from 2,300 - 6,600 ft.

tuberosa

South America

Yellow

(700 - 2,000 m).

Campos Rupestres montane savanna in moist

sand/peaty soil mixtures at an altitude from 5,249 -

uncinata

South America

Light Purple

6,600 ft. (1,600 - 2,000 m).

Sandy, quartz-based peaty soils atop quartz at

violacea

South America

Purple

around an altitude of 5,906 ft. (1,800 m).

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