Today we celebrate Family Day, and what a great day to shine the spotlight on a few of our favourite plant Families.
What is a plant family?
To bring sense and order to the millions of plant species on our Earth, plants that share similar morphological and genetic characteristics are grouped together. Plant families serve to group together broadly similar genera (ending in -aceae).
To learn more about the classification of plants check out the article below.
There are hundreds of different plant families and knowing a few of them can be very useful to help identify certain species, assist in planning your vegetable garden and crop rotation, and it can help in selecting appropriate plants for specific landscape purposes.
Here are five plant families that are easy to get acquainted with. Head into the garden and see if you can identify a few!
Asteraceae | Daisy family
Asteraceae is the largest flowering plant family with more than 25 000 plant species worldwide. They display remarkable variation in growth form and morphology. Plants in this family range from annuals, perennials, shrubs, trees, scramblers and even aquatics.
To identify plants within this family look for composite flower heads (daisy-type flowers), made up of many florets.
Examples of plants in this family are Calendula, Dahlia, Zinnia, Echinacea, Gazania and Chrysanthemum.
Brassicaceae | Cabbage family
Brassicaceae is also a large family and includes many familiar vegetables like cauliflower, broccoli, mustard, rocket and radish.
Arugula flower. Image by Etienne GONTIER from Pixabay.
Brassicaceae was previously known as Cruciferaceae, referring to the cruciform flower structure - four petals in a cross shape.
Most plants in this family are herbaceous. The inflorescences are usually terminal and flowers feature four long and two short stamens (male reproductive organ). The fruits are pod-like (known as siliques) with seeds in rows separated by a thin wall called a septum.
Iridaceae | Iris family
Plants in the Iridaceae family are mostly grown as ornamental plants and a few examples include Iris, Dietes, Crocus, Gladiolus, Freesias and Moraea.
Plants in this family are mostly herbaceous perennials with underground storage organs including corms and rhizomes. The leaves are long and thin, very often arranged in two rows and form a fan shape.
The flowers have six petals, in two rings of three, with three stamens opposite the three outer petals. A very prominent characteristic of this plant is that the seedpod forms behind the flowers and is composed of three chambers with two rows of seeds.
Seedpod formed behind the flower.
Dried seedpod of Dietes grandiflora.
This family is well-represented in southern Africa with 38 out of 65 genera recorded in our beautiful country. Remarkably, there are 707 species (27 genera) growing in the Cape Floral Region alone.
Lamiaceae | Mint family
If you have herbs growing in your garden you are definitely familiar with this family. Examples of plants in this family include rosemary, lavender, sage, Leonotis, Coleus and Plectranthus.
Plants within the Lamiaceae family are very easy to identify by their square stems. The leaves are arranged in pairs running up the stem. Foliage is also aromatic, often hairy or with scent glands.
Hairy leaves of Plectranthus.
The flowers have two lips, generally, the upper lip has two lobes and forms a canopy over the lower lip. The lower lip usually consists of three lobes and form the perfect landing strip for pollinators. Each flower produces four seeds and with no seedpod, the seeds are free to roll out when they are ripe and ready to go.
Malvaceae | Mallow family
Plants in the Malvaceae family include herbaceous plants, shrubs and trees. A few examples of plants in this family are cotton, Hibiscus, okra, Hollyhock, and cacao.
The flowers of the Mallow family are quite large and easily distinguishable by the five unjoined petals. The flowers are usually rolled up together in bud. The female and male reproductive organs form a long tube that protrudes from the centre of the flower. The stigma (female reproductive organ) is branched.
The branched stigma of a Hibiscus flower.
Interestingly, these plants contain a natural gum so when crushing any part of the plant between your fingers you will notice a slimy substance.