Arisaema nepenthoides
Yellow cobra plant, Nepenthes like cobra lily
Also known as Arisaema ochraceum
- Height × spread
- 0.9m × 0.5m
- Position
- Tolerates full sun, likes part shade, tolerates light shade
- Hardiness
- Mild winter to -5C (RHS H3)
- Flowers
- Spring, Summer
Availability
Please ask in store about availability
Many plants are seasonal. Call 01234 567890 to check current stock.
About this plant
This has a few large leaves, usually one or three of them. They are digitate, like the leaves of a horse chestnut and glossy green, purplish on their under-side, held on a long vertical stalk. It blooms in late spring or early summer when the impressive hooded flower arises, standing erect over the leaves head bowed like the cobra. It is greenish-yellow with a slightly sinister appeal. A long slender tail like appendage dangles from the flowers mouth. This is an extension of the 'flower', called the spadix, that is held within the hooded cup. The whole edifice has a vaguely interesting, unpleasant smell, likened by a leading authority to that of pond water. This reaches around 90cm (3ft) height when in flower, with 50cm (20in) spread. Give this soil that is humus rich and moist but well drained, dryer when the plant is dormant. It likes neutral or acidic conditions and a cool site in partial or dappled shade.
- Flower colour
- Brown, Green, Yellow
- Foliage colour
- Green
- Variegated
- No
- Scent
- No
- Shape
- Oval
- Height
- 0.9m
- Spread
- 0.5m
- Season of interest
- Autumn
- Flowers in
- Spring, Summer
- Evergreen
- Deciduous
- Garden style
- Exotic garden, Conservatory
- Sun or shade
- Tolerates full sun, likes part shade, tolerates light shade
- Soil type
- Clay, Loam (normal)
- Soil pH
- All types
- Drainage
- Moisture retentive soil, Well drained soil
- Hardiness
- Mild winter to -5C (RHS H3)
- Borders & containers
- Borders and containers
- Hazards
- Yes, potentially harmful; Humans: Harmful if eaten; skin & eye irritant
AutumnNow
Autumn - late · Outdoors
Apply a protective mulch
Protect the crown of the plant in winter in areas that are prone to frost and cold. For short term protection a fleece can be used, otherwise fill mesh sacks with masses of straw and secure them over the plant's crown.
The 'traditional method' is to put wire or other netting over the plant, layer plenty of straw on top of this and then secure the whole with more netting.
Spring
Spring - late · Outdoors
Feed with slow release fertiliser
Apply a general purpose slow release fertiliser, spreading it around the root area of the plant as it is coming into growth. (Or apply a liquid feed at regular intervals throughout the growing season.)
This is a simple way to provide a nutrient boost as a single annual procedure.
Spring-Autumn · Outdoors
Water to keep the soil moist
For best results, this plant needs soil that is always moist. Water deeply and regularly as soon as soil appears dry. Even for established plants in the ground, a dry week can cause problems with some soils. Check plants in pots more often, especially in hot weather. Or install an automatic irrigation system which will do the hard work for you, even when you are away on holiday.
Without regular watering some plants never fully regain their beauty.
Summer
Summer · Planting
Remove offsets to create new plants
Offsets are small plants or shoots that develop around the parent plant. They should have developed a root system of their own before they are detached. They can be planted directly, or grown in pots if so small they could be 'lost' in the garden.
Offsets may be used to replace an aged parent plant, to extend or establish a colony, or can be given away or sold.
Planting & general
Outdoors
Water with rain water
This plant needs rain water or soft water (the minerals in alkaline or "hard" water are harmful). This is especially important for plants in pots.
Compost · Planting
Ericaceous compost
This plant requires acidic (ericaceous) soil. Where the soil is not acidic, or when planting in pots, use an ericaceous compost.
Found in
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Elegant cobra lily
Arisaema consanguineum subsp. kelung-insulare
Cobra lily
Arisaema exappendiculatum
Appendixless cobra lily
Arisaema serratum
Japanese cobra lily
Arisaema sikokianum
Shikoku cobra lily
Arisaema tortuosum
Tortuous cobra lily, Tall cobra lily
Arisaema amurense subsp. robustum
Robust cobra lily