Say ciao to the Brassicas!

Sunday, 30 July 2017

Vase on the desk of Tricia de Nicola in Sydney

As my brain tried to grapple with the mysteries of the 'imperfect subjunctive' tense in my Italian lesson last week, a pretty bunch of flowers on my teacher's desk caught my eye. Shiny green leaves were paired with some unusual purple blooms, which at first I took for some sort of rare Camellia japonica cultivar: upon closer inspection I realised they were kale 'blooms' (actually rosettes of leaves). These have become widely used by florists in recent times, and they last for ages in a vase. Kale belongs to the vast Brassica or mustard family (Brassicaceae, previously called Cruciferae), an interesting group of plants that contains both ornamental and edible plants; indeed, kale can be had in both forms!

Erysimum mutabile

The decorative plants within the family are rather old-fashioned flowers, long grown in English cottage gardens. Whilst not all of them flourish well in Sydney (I failed miserably with Arabis, Hesperis, Iberis, Crambe, Aubretia, Alyssum and Cardamine in my cottage garden years), some do, and I enjoy having them in my garden as a reminder of that part of my gardening journey. All have simple, four-petalled flowers that resemble a cross, which are attractive to beneficial garden insects: another great reason for growing them. One of them, a delightful shrubby perennial wallflower (Erysimum mutabile, syn. Cheiranthus mutabilis), is just starting to bloom now, and will continue all through spring. The original species (ht 80 cm, pictured above) has flowers which open pale yellow then age to mauve. The cultivar 'Winter Joy' has pretty all-mauve flowers and 'Apricot Twist' is an attractive orange-bloomed version. These plants, hailing from the Mediterranean, enjoy a sunny, well-drained position, on the dry side, with a little lime added to the soil - in fact most members of the family seem to like a bit of lime! They need to be cut back after flowering to keep them compact, but like many such shrubby Mediterranean perennials, they will only last a few years: propagate from cuttings. These wallflowers combine well with other plants from the Mediterranean that flower at the same time, such as Iris germanica, French lavender (Lavandula dentata) and Marguerite daisies. There are biennial forms of wallflowers, which I recall growing in my parents' garden. They also grew gorgeously scented biennial stock (Matthiola incana), another member of the Brassicaceae.

Lunaria annua var. albiflora Alba Variegata

Lunaria annua, often known as honesty, is also a biennial plant from the Brassicaceae (ht 30 cm) that grows well in Sydney gardens, self-seeding from year to year. The basic plant has plain green leaves with clusters of purple flowers, and is a pretty thing; however, some of the cultivars are more interesting. I like Lunaria annua var. albiflora 'Alba Variegata' (pictured at left), which has white and green marbled leaves and white flowers. I grew it from seed many years ago and it still comes true from seed fairly well. The plant will grow quite well in shaded sites and doesn't need any special cosseting. It usually takes a full year to achieve flowering stature: sow the seed in spring for blooming the next year. It flowers around late September or October. The branched seed pods that follow the blooms are decorative in the garden in their own right.

Lobularia maritima Snow Princess

An annual plant, Lobularia maritima, often known as sweet Alice or alyssum (ht 20cm), has honey-scented fragrant little bobble flowers and is another old-fashioned favourite from the Brassicaceae. Like honesty, it is a determined self-seeder. The most common form is white, but there are also pink and purple varieties. It too is a Mediterranean plant and enjoys dryish, sunny positions in the garden. It is often used as an edging plant and blooms for many months. I have an interesting form called 'Snow Princess' (pictured above), which is said be a perennial form, growing robustly to a wide mat. It can be cut back by half when it gets untidy and will regrow strongly. It has crisp white flowers all year round, with a strong scent. Another annual from the family that I used to grow was Virginian stock (Malcolmia maritima), a dainty plant with cute lilac blooms.


The Brassica family contains many highly nutritious crops with many health benefits, which seem to grow best in the cooler months of the year, including cabbages, cauliflowers, brussels sprouts, broccoli, turnips, kohlrabi, radishes and swedes. I have never tried cultivating any of these vegetables but I do sow seeds of some of the easy-to-grow leafy Brassica crops in my garden in winter in spots where I have big gaps, such as where my Dahlia plants are lying dormant. In general, these types like moist, fertile soil to support their rapid growth: poor soils result in bitter, tough leaves. They will all regrow after being harvested so that a number of cuts can be made; but it is a good idea to make successive sowings to ensure a long period of supply, as the plants eventually become exhausted! All of them can be grown successfully in containers. Allowing a few of the plants to progress to flowering will attract beneficial insects into the garden. Rocket (Eruca vesicaria syn. Eruca sativa), with its peppery leaves, is perhaps the best-known member of the family, being a quick-growing leafy green for salads, pesto and pasta dishes. Kale (Brassica oleracea Acephala Group) has become a trendy food in recent years, and is used in salads, stir-fries and many vegetable dishes. The many decorative forms of kale, with curled or crinkly and/or coloured leaves of various shapes and sizes, can look most attractive in the garden - as well as in a vase!

Land cress

The various forms of cress are also nutritious members of the family, including true watercress (Nasturtium officinale), garden cress (Lepidium sativum, familiar to many from childhood, when it was grown on a piece of cotton wool as 'mustard and cress') and land cress (Barbarea verna). There are other leafy members of the family that are sometimes called 'Asian greens', including bok choi or pak choi, mizuna, komatsuna and tatsoi, which all seem to be cultivars of Brassica rapa. All these plants are valuable for stir-fries and salads.

All in all, the Brassica family is an interesting and useful clan!