Crop Rotation

The main purpose for crop rotation is to prevent pests and diseases from building up to the point where they cause problems.

Different crops are susceptible to different pests and diseases, so by moving them around the pests and disease specific for each group die off.

The added benefit is that some vegetables actually deposit nutrients into the soil, to benefit the next group to be planted there. The best example of this is the Legume family (Peas & Beans), their roots deposit nitrogen into the soil.

Some family groups grow harmoniously with others, known as companion planting. This has been shown to prevent some pests and also improve the flavour. Whilst other groups planted together can actually stunt growth. So it’s really important to know your family groups.

Knowing your Veg Families

Vegetables are divided up into family groups. The main ones are as follows:

Cucurbitaceae – Commonly known as Gourds – Cucumbers, summer and winter Squash and Melon.

Fabaceae – Common name Legumes – Peas and beans.

Baassicacae – Mainly known as Brassicas – Broccoli, Cabbage, Cauliflower, Kale, Brussels sprouts.

Liliaceae – The best known veg in this group are Alliums – Onions, Shallots, Chives and Garlic. But it also incudes Asparagus.

Chenopodioideae – Beetroot, Swiss Chard and Spinach.

Apiaceae – Carrot family – Carrots, Parsnips, Celery, Celeriac, Fennel, Coriander.

Solanaceae – Common name Nightshades – Incuding Potaotoes, Tomatoes, Peppers, Chilies and Augergines.

Polygonaceae – Mainly ornamental plants. But a couple of familiar edibles are Buckwheat and Rhubarb.

Lamiaceae – Mainly herbs – Perennials such as Basil and Oregano. Shrubby types such as Mint, Thyme Rosemary and even Lavender.

My Crop Rotation

I have six raised vegetable beds, but two of them are given over to permanent perennial crops. Asparagus and autumn fruiting Raspberries.

The other four change every year with crop rotation. Only one bed is manured in the autumn, as not all plants like the same nutrients.

Bed One

The Cucurbitaceae family of squashes go in first, as they are the greediest plants, needing the maximum food. I only grow two plants in this bed as they need a lot of room. I usually grow one courgette and one patty pan.

Bed Two

The following year the Fabaceae family of legumes are planted there. They also like a lot of fertility, but are actually a giving plant as they deposit nitrogen into the soil. In this bed I grow broad beans, climbing beans, mangetout and sugarsnaps.

Bed Three

As the Baassicacae family of brassicas love nitrogen they follow on next. These crops need the nitrogen to produce their large leaves.

I always grow purple sprouting broccoli, and Italian kale ‘Calvolo Nero’. Sometimes I grow brussels sprouts and cabbages.

I grow my onions, shallots and garlic, from theLiliaceae family in with the brassicas. Their punget aroma is thought to deter white fly and white cabbage butterflies – but I find a large netted cover works rather better against the butterflies!

Bed Four

Finally, anything classed as a root goes in on the forth year, to use up the last of the nutrients. If the soil is too rich the roots tend to split, leading to some amusing vegetables.

The roots I tend to grow together are, beetroot from the Chenopodioideae family. And Celeriac from the Apiaceae family.

When the roots have finally all been picked, the bed is manured, ready to start all over again.

Plants not featured in my crop rotation

It’s not always appropriate or possible to rotate crops. So to negate problems from pests and disease, you can either grow crops in pots. Or make sure you check your plants regularly to nip any problems in the bud. It is also important to use very good hygiene practices.

The herbs from the Lamiaceae family, I mainly grow in pots or mixed into my flower boarders.

I don’t rotate any plants from the Solanaceae family. As I grow potatoes in bags. And my peppers, chillies and aubergines are grown in pots.

My tomatoes also from the Solanaceae family are grown directly into the ground, but in the greenhouse.

To avoid problems I dig out and replace the compost every other year. And make sure the greenhouse has a good clean each year.

If any pests do start to build up in the greenhouse, for me it’s white fly and spider mites. I use biological control, this involves buying, either predators or parasites that eat your pests whilst leaving your precious crops alone.

I use ‘Encarsia formosa’ wasps for the white fly control. And ‘Phytoseiulus persimilis’ for controlling the spider mites. All very gruesome but totally natural and organic.

Carrots from the Apiaceae family, I also grow my in the greenhouse. They follow on after the tomatoes have finished, and grow over winter.

Rhubarb from the Polygonaceae family, grows in a border with fruit bushes.

Draw up a plan

So the best way to sort out your crop rotation is to sit down and draw up a plan.

Start by writing down what you want to grow. Don’t just grow what you think you should grow, grow what you really like.

Once you’ve made your list, arrange them into their plant families. From that point it should be easy to work out which plants go into which bed.

Now you just have the great pleasure of shopping. You just need to decide whether to grow from for seed or buy some plug plants. Either way, you won’t regret it as there’s nothing quite like going into your garden, and picking your own homegrown veg!

Stay safe and happy gardening.