The family name is Malvaceae, but the different varieties have a variety of botanical names, can grow up to 2 metres tall, or crawl along the ground, or be various sizes in between. While the seed containers on all of them are small and disk shaped, they vary in makeup and number of seeds.
Malva sylvestris is known in Europe as Common Mallow. Its flowers are pink with red or purple veins, deeply notched petals can be 3cm long, and grow in clusters in the leaf axils.
It possibly originated in Greece, where it decorates many areas of the landscape, including waste ground and sometimes rocks and sand dunes. It is a perennial and in NZ, at least, can grow to around 120cm tall. The leaves are generally 5-lobed and slightly plicate, which means each lobe has a somewhat pleated look up the centre. Stems are woody and sprawl outwards, with the ends curving upwards. Long taproot. Flowers November-April.
Apparently leaves, seeds and flowers are all edible, unless the plant is grown on nitrogen rich soils, in which case it contains high levels of nitrates in the leaves. Its long list of medicinal properties reads like a tongue twister, and to cure your particular ailment you can put it on externally as a poultice, eat it or drink it as tea – a regular cure all in fact!
Modiola caroliniana or Creeping Mallow is the ground-hugging variety often found in less manicured lawns, along paths, on bare ground and in open pasture. It can be an annual, biennial or perennial and favours the warmer parts of the country. It has small (about 15mm) single flowers which range from orange to orange-red, and flowers from October-March.
While in NZ it appears safe for animals to eat, it has been suspected as a cause of staggers in Australia and in America, from whence it came originally. Its leaves are light green and flattish, round in outline with indented edges. Its habit of putting down fibrous roots at every node makes it difficult to pull out completely, as any bits left behind are quite self-contained and continue to grow.
Malva parviflora, small flowered mallow, is the ‘middle man’, growing semi-erect up to 50cm tall as an annual. It is probably the most common mallow growing in NZ. In the US it is known as Cheeseweed, because its seed pods resemble a segmented cheese wheel. The flowers are tiny (about 4-5mm) and vary from pale mauve to whitish, with 5 petals which are slightly longer than the sepals. The dull green leaves have 5 or 7 lobes on long stems radiating from the rootstock. Stems can grow to 60cm and, like M.sylvestris, curve up at the ends. This variety favours bared ground near trees, stockyards, gateways, and waste round. Flowers September-April.
The treelike variety Lavatera arborea can grow to 2m, with a single main stem. As it grows the lower leaves drop off leaving just a tufty head and a stem which can grow to 10cm thick. The large, velvety leaves can be up to 20cm in diameter and, like Common Mallow they can have 5-7 lobes, each folded along the mid-rib. Flowers are about 4cm in diameter in lilac or deep pink with darker veins. Again the fruits are round, formed of up to 8 capsules. Often seen growing on roadsides, like the other varieties it can be found on waste or cultivated ground and in coastal areas. The long flowering season is from August-May.