Rotating your crops

Crop rotation results in better vegetables and flowers. Photo: Gillian Vine.
Crop rotation results in better vegetables and flowers. Photo: Gillian Vine.
What to do in your garden this week.


Crop rotation may sound overly scientific for the ordinary gardener, but it is an important way of getting the most from the vegetable garden while minimising the risk of diseases such as club root in cabbages or basal rot (caused by Fusarium oxysporum) in onions, garlic and leeks.

Designed so crops can take different minerals from the soil each year, good rotation will take account of chemical and physical differences between plants. The basic rule is never to grow plants from the same family or type in the same spot two years in a row.

Leaving aside perennial vegetables such as rhubarb, globe artichokes and asparagus, which stay in the same plot, divide your garden into three areas.

Make a list of what crops can be grouped: potatoes, celery, leeks, carrots, parsnips and beetroot in group one; peas, beans (all types), onions and spinach in group two; and brassicas (including Brussels sprouts, cabbages, broccoli, cauliflowers and kohl rabi) in group three. Grow each group in separate plots this season.

In the second season, grow taprooted plants (group one) in the plot previously used for peas and beans. Put peas, beans and the onion family where the brassicas were and put brassicas in the remaining part of the garden. Year three sees brassicas in plot two, taprooted plants in bed three and onions in the third section.

A garden diary may make it easier to remember the movements, or draw a computer-generated plan and mark what was sown or planted where, with planting or sowing dates.

If the weather is reasonably dry, dig vacant ground roughly, but do not try to cultivate it too finely at this time of the year or it can set like concrete as it dries.

Winter is a good time to sharpen and clean garden tools, and repair or clean garden furniture and shelves in the greenhouse or shed.

Put green rubbish in the compost heap, but take woody, prickly or diseased material to a landfill.

Even in midwinter, rhubarb and asparagus beds can be planted, weather permitting. Dig the ground deeply, add plenty of bulky manure plus some blood and bone and plant with the crowns about 2.5cm below the surface.

Jerusalem artichoke tubers, shallots and garlic can also be planted.


Crop rotation in the flower garden is also possible.

Stocks and wallflowers in mass displays exhaust the soil in similar ways to vegetables and should not follow each other. Likewise, if dahlias are grown in the same soil year after year, they will make excessive demands on some soil elements and plant quality will drop.

Ideally, dahlias, gladioli, pansies, violas, tulips, hyacinths and narcissi should be planted in different areas of the garden each year.

Rose-planting time has arrived and nurseries will soon be full of this popular shrub.


Winter spraying of apples and pears with a winter oil spray will help control woolly aphids, scale insects and red spider.

If you prefer not to spray, attracting waxeyes to the garden by putting a shallow container of sugar water on or near fruit trees will encourage them to clean up bugs.

Good garden hygiene is important in preventing or controlling disease.

Fruit remaining on trees should be removed.

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