Gardening | Onions versatile performers in the garden and kitchen

GARDEN FAVOURITE: Onions like it bright, so plant them in a spot that gets at least six hours of sun a day.

Onions are generally easy to grow and can be harvested between six and eight months from planting from seed.

Seeds of onions prefer to be planted out in cooler soils so they can become established before periods of hotter weather. Seedlings can be thinned so that plants are between 5cm and 10cm apart.

When planning the vegetable garden it is sometimes useful to consider combinations of vegetables that may or may not result in successful cropping. Onions should not be planted directly next to rows of peas or beans. It would be preferable to plant a row of carrots between the two vegetable types.

A sunny position should be chosen, ideally one that has at least six hours of sun a day. Excess feeding and over-watering should be avoided as it will result in a lack of bulbs and the possible rotting of the plants. As plants begin to mature, the onions should be on the surface of the soil and not covered. Avoiding placing mulch around the bulbs will help achieve this.

Plants will be ready for harvesting when the tops start to dry and fall over. The bulbs should be pulled from the soil and left to dry for a few days. They can then be stored in a cool, dry, airy place. The use of a net bag would be suitable.

A range of colours is available. Brown onions have a strong and pungent flavour and are usually good keepers for storage purposes. White onions are milder but still have a good flavour. They keep fairly well. Red onions are suitable for use raw in salads and sandwiches, because of their mild flavour.

After cutting the top off an onion, instead of discarding it, the top can be planted into soil where it will eventually form a new plant.

Spring onions are grown for their tops. They do not form a bulb. Instead, their green tops are used. Spring onions can be sown all year round. Shallots, garlic and chives are also members of the onion family.

Fab foliage

A garden that is attractive all year round, rather than just when there is a flush of spring flowers, will usually feature a variety of foliage colours, with the use of annuals to provide a splash of colour.

Many of these plants look very effective when they are placed against a grey background. Plants with silver or grey leaves generally prefer free-draining soils and sunny positions.

Many are frost and drought resistant.

Lamb’s Ears (Stachys Byzantium), Catmint and Snow-in-Summer are all groundcover plants. Wormwood (Artemisia ‘Powis Castle’) is a taller growing plant, while Cotton lavender (Santolina), Curry Plant (Helichrysum) and Cat Mint (Nepeta) are more compact shrubs. Curry Plant produces an aroma very suggestive of a curry being cooked, hence its common name.

A selection of native plants also feature grey/green leaves.

Grey Honey Myrtle (Melaleuca incana) grows to about two metres in height and produces yellow flowers on long, pendulous stems, mainly in late spring. Several wattles also produce grey foliage. Acacia baileyana (Cootamundra Wattle) produces ferny foliage and the foliage on Acacia cultriformis is smaller, with flowers in a yellow ball shape.

A grey-foliaged hedge can be grown through the planting of varieties of Coastal Rosemary (Westringia), including Westringia fruticosa Jervis Bay (dwarf form) and Westringia glabra.

Best banksias

Banksias are native plants that will soon begin to produce their very attractive cones. These can vary in colour from pale yellows through to deep oranges and reds, sometimes with black features.

The flowers form in autumn and reach their best in late autumn through to spring. As they are full of sweet nectar they are a good food source for native birds, especially honeyeaters, and small mammals. Growth habits range from prostrate, ground cover forms through to small trees. Banksia Giant Candles is a hybridised form from Banksia ericifolia and Banksia spinulosa. Its flowers can grow up to 40cm in length and are bright orange.

Banksia Birthday Candles is a dwarf form that can be covered with flowers. Banksias serrata (Old Man Banksia) and Banksia spinulosa var. collina are also available in a dwarf form and is ideal as a hedge, growing to two metres in height. Banksia ericifolia (Heath banksia) can grow to five metres, although it is often much smaller. It is very hardy and will survive extremes of cold. Banksias integrifolia (Coast banksias) can also survive frosts and salt spray. It produces pale yellow flowers in late summer. Banksias usually grow best in well drained soils in a sunny position.

Most respond to light pruning, and those which form a woody rootstock (lignotuber) can be heavily pruned. Only low phosphorus fertilisers should be used.

Orchid care

Gardeners with cymbidium orchids should feed them now to encourage the formation of flower spikes. A favourite source of food for this type of orchid is Campbell’s Orchid Food – Yellow form, as it has the correct balance of nutrients and elements that are required for flower formation.

Using a general fertiliser could lead to the production of extra foliage rather than flowers.