Jerusalem cherry

Solanum pseudocapsium

Jerusalem cherry is an erect, bushy, evergreen shrub, often grown as a winter-fruiting annual. It has wavy-margined, elliptical leaves, which are glossy and dark green. In summer, it bears white flowers similar to those of tomatoes or peppers. These are followed by long-lasting, spherical red, yellow or orange-red fruit.


Johnson grass

Sorghum halepense

Reed-like perennial up to 3m high with an extensive system of branched rhizomes. The stems are stout and erect. Smooth leaves up to 60cm long. Large, open, reddish-brown inflorescences up to 40cm long from November to April. Wilted foliage and young sprouts are poisonous.


Jointed cactus

Opuntia aurantiaca (Cactaceae)

A spiny, many-branched, spreading cactus growing up to 1,5m high, with underground tubers. No leaves but flattened leaf-like stems are bright green, sometimes tinged with reddish-purple. Bright yellow flowers appear from November to January followed by reddish succulent fruit.


Kahili ginger lily

Hedychium gardnerianum (Zingiberaceae)

A vigorous plant up to 2m high. Broad, bright green or greyish-green leaves which sheath the stems. Showy, fragrant flowers in spikes up to 35cm long from January to March. Flowers are yellow with red protruding stamens.


Kangaroo wattle

Acacia paradoxa

A densely, leafed spiny shrub originating from Australia, grows up to 3m tall and 3.5m wide, and it is only present on Devil's Peak on Table Mountain, in the Western Cape. Bright yellow fluffy blooms of globe-shaped flowers in dense terminal sprays appear in August to October. The short- stalked seed pods are brown, straight or slightly curved and are covered in white-woolly hairs.


Kariba weed

Salvinia molesta (Salviniaceae)

An aquatic, mat-forming, free-floating fern with horizontal stems up to 25cm long. Green to yellow-green oval leaves form in pairs with dense upper surface cover of hairs. Feathery, root-like leaves hang down in the water


Karri

Eucalyptus diversicolor (Myrtaceae)

A tall, dense, massively branched, evergreen tree 25-58m high with smooth bark that is grey-blue in colour with orange-yellow blotches. Dark green leaves which are glossy above and distinctly paler beneath. Cream flowers appear from May to December. The fruit capsules are globular and brown. This tree invades forest clearings, fynbos, roadsides and water courses.


Kikuyu grass

Pennisetum clandestinum

Kikuyu grass is a rhizomatous grass with matted roots and a grass-like or herbaceous habit. It is a prostrate perennial, which may form a loose sward up to 46cm high when ungrazed, but under grazing or mowing, it assumes a dense turf. The grass spreads vigorously from rhizomes and stolons, which root readily at the nodes and are profusely branched. 


Knotweed

Persicaria capitata

Knotweed is a mat-like, perennial, herbaceous plant with a slender, woody rootstock and long, creeping, rooting stems. It is found growing on roadsides, dry banks, slopes and in open areas, preferring full sun. It negatively impacts on the environment by forming a dense carpet, replacing most indigenous vegetation. 


Kudzu vine

Pueraria montana (Fabaceae)

Vigorous, deciduous climber up to 18m high with a large tuber. Very long, hairy vines. Light green, finely hairy 3-palmate leaves. Reddish-purple, fragrant flowers in spikes up to 30cm long from March to April. Flattened pods covered with long, rusty-brown hairs