Crop Rotation



Crop rotation is important because different types of plant draw different nutrients from the soil. 

A good crop rotation plan will help to limit pests and diseases. Here are some common cycles (in order of planting):

  • Three year: legumes and fruiting vegetables, brassicas, roots and onions and leaves
  • Four year: roots, potatoes, legumes, brassicas
  • Five year: brassicas, peas and beans, potatoes and fruiting vegetables, onion family, root and stem vegetables

It’s OK to switch from one system to another, and vegetables that don’t match a category (e.g. squash, sweetcorn, spinach) can be fitted in wherever convenient). 



Growing with Children


Allotment plots are an ideal learning environment for children and there are many ways of involving them in the process from planning through planting and harvesting, and then to prepare produce.

The National Allotment Society has come up with the idea of engaging children at this time of year to grow an allotment rainbow. If you need help in thinking of the kinds of plants to provide all of the colours they have the following suggestions:

  • Red – red lettuce, rainbow chard, red carrots, tomatoes, red pepper, poppies
  • Orange – carrots, orange tomatoes, orange peppers, butternut squash, pumpkins marigolds, Californian poppies
  • Yellow – yellow pepper, yellow tomatoes, sweetcorn, yellow carrots, marigolds, poached egg plants
  • Green – spinach, kale, chard, peas, beans, broccoli, cucumber, courgettes, basil
  • Blue/Indigo/Violet – aubergine, purple cabbage, purple carrots, purple potatoes, purple basil, sweet peas, borage, cerinthe

For more information about involving children on the plot see the allotment gardening web-site:




Good compost is invaluable. 

Compost introduces nutrients to support plant growth. It lightens heavy soils, helps soils to retain moisture, and helps control plant diseases. 

Compost falls into two broad categories: garden compost and potting compost.

Garden Compost

Garden compost refers to the material that we can all produce when we gather kitchen and garden waste and leave it to decompose. Home-made compost ideally contains equal amounts of green materials (grass cuttings, fruit and vegetable peelings, young plants, animal manure, etc. which have a high nitrogen content) and brown materials (leaves, straw/hay, woody shoots, cardboard and paper). 

As the vegetable matter rots it generates heat. The heat accelerates the decomposition process resulting in rich, dark organic matter that can be dug into the soil or applied as a mulch. Adding materials such as nettles, comfrey and urine to compost can also help to accelerate the process. Oxygen is a key element in the decomposition process and garden compost should be periodically turned with a fork to introduce air.

Making compost helps the environment: reducing numbers of bonfires, cutting down on waste, and reducing demand for manufactured products. It can also provide a habitat for hedgehogs, beetles and slow-worms, many of which feed on slugs act as natural pest controllers, reducing the need for chemical pesticides.

Potting Compost

Potting compost is the bagged material that we get from garden centres (and The Shed!). Bagged compost is available in several forms to serve specific purpose – multi-purpose compost can be used at all stages in the growing cycle, seed compost is designed to assist germination, ericaceous compost is designed for plants which prefer acid soils, tomatoes and strawberries are planted directly in grow bags. Peat free compost is widely recognised as being more environmentally sustainable than those containing peat.



The purpose of fertilisers is to re-introduce chemicals to the soil that are absorbed by plants as they grow. 

Chemical Fertilisers 

The main elements, all of which are available from The Shed, are:

  • Nitrogen, which promotes the growth of leaves and stems (ideal for brassica, leeks, onions and leaf salads.
  • Phosphates, for root growth, flowers and seeds (carrots, parsnips, swedes and turnips).
  • Potassium/Potash, which helps plants to develop resistance to disease and build up sugar/starc (potatoes, beetroot, sweetcorn and soft fruits).
  • Trace elements are taken up in minute quantities by plants and include magnesium, zinc, iron and copper.

Crop rotation is important because different types of plant draw different nutrients from the soil. 

Organic Fertilisers

  • Manure – an excellent source of nitrogen, but use well-rotted manure or pellets as fresh manure can damage plant roots
  • Bonemeal – high in phosphates, ideal preparation for planting perennials
  • Fish, blood and bone – a general fertiliser to stimulate growth during spring/early summer
  • Hoof and horn – a slow release fertiliser that is high in nitrogen
  • Liquid feeds – soak comfrey or stinging nettles in a water butt to make a ‘tea’ (some people use old pillow cases for tea bags!) and add (5-10%) when watering plants 
  • Gypsum – ground calcium based rocks which ‘lighten’ clay soils
  • Wood ash (bonfire residue) – a source of potassium for applying directly to soil or adding to the compost heap 
  • Seaweed – increases pH of soil (reduces acidity) and contains calcium and magnesium


The following table can help you identify which type of fertiliser is needed by which plant (or where symptoms of poor plant development have previously arisen), together with how it can be provided both organically and inorganically.



Local Manure


Manure is a great way of improving soil condition, available from the following local sources... 

  • Raybrook Riding, Bluebridge Road, Brookmans Park, AL9 7SX. Various ages of manure bagged for collection plus a “heap” which may be excavated. Parking for cars and trailers but please telephone before you arrive to check on availability. There is no charge, but donations to Horse Rescue are welcome. 

  • Welwyn Equestrian Centre, Arnolds Farm, Pottersheath Road, Welwyn, Herts, AL6 9SZ. They have two manure heaps which can be excavated for collection but you will need to supply your own bags and call the centre to notify them you are coming.

  • Riding for the Disabled, Rectory Road, Welwyn Garden City (opposite The Red Lion pub on the B197). Collect it yourself and you can make a donation to the charity on your visit.


Green Manures


Autumn is the time to plant green manures. These plants tend to grow quickly and either scavenge nutrients that otherwise might be washed out of the soil or take nitrogen from the atmosphere and transfer it to the soil through their root systems. The roots also improve the structure of the soil, and green manures also prevent weed growth by blocking out light to growing weedlings. 

The main types of green manures are listed below:

  • Clovers can help to fix nitrogen within the soil - should be planted between April and August.
  • Winter Tares (also known as vetches) is a good source of nitrogen and should be planted by September.
  • Phacelia (March - September) and Lupins (March - June) produce flowers which support bees and other insects as well as boosting the soil.
  • Italian or Hungarian ryes (August – October) are good to smother areas that have become overgrown with weeds and grows well through winter (but can provide shelter for slugs and snails).
  • Field beans can be planted as late as November and are good for heavy soils.
  • Mustard should be planted by the end of September and should be dug in after up to two month’s growth (or left as a mulch if the foliage is frost damaged).
  • Mexican marigolds (Tagetes Minuta) can be used as a green manure but its greatest benefit is that it suppresses bindweed and is best sown in spring.

Dig green manures into the soil in the spring while they are still soft and they add nutrients to the soil and enhance the activity of worms and other wildlife below the surface of the soil. Leave for at least two weeks before planting out crops.


Early Summer Pests


Slugs and snails – these seem to be ever-present but are more mobile in warmer weather, particular after periods of rain. Leaf crops like cabbage and lettuce are favourite targets. Copper rings, crushed eggshells and beer traps are traditional solutions. Conventional alternatives include coffee grounds or bran. Slug nematodes are a natural scientific solution but can be quite expensive and require a combination of warm weather and moisture (which are certainly not guaranteed at this time of year!). 

Aphids – will be sucking the sap from many types of fresh edibles now that the early signs of summer. You can squash them with your fingers or plant strong scented plants nearby (e.g. garlic) to deter them. Ladybirds are their natural predators and you can buy ladybird pupae to spread around your plot and will welcome a rich food supply when they hatch. 

Asparagus beetle – these visually attractive beetles produce small grubs which can devastate asparagus when it is resting and developing as a fern. The adults can be picked off as they develop. To prevent re-emergence next year, clear away the stems in early winter and burn them (if they are stored the bugs may be able to find shelter).

The 'No Dig' Method

Soil is a living mixture of diverse organisms and works better when it’s not disrupted. No-dig gardening can bring many benefits to your plot and is gentler on your back than traditional methods of growing vegetables. Nutrient rich materials – compost, manure, etc. – are applied at normal rates but only at the surface of the soil. Worms and other organisms do the work of bringing the nutrients into the ground.

The basic requirements are:

  • Avoid treading on areas where plants will be grown – this generally requires beds to be no wider than 1.2m (4’)
  • Regularly apply organic matter – well rotted horse manure, spent mushroom compost or maybe garden compost - over the ground surface to a depth of about three inches compost, manure and mulches
  • Apply nutrient rich fertilisers in the spring when plants are growing at their fastest and the weather is less likely to wash them away
  • Gently ruffle the surface when preparing seed beds
  • When beginning beds, apply opaque coverings (cardboard, carpets or sheeting) to kill of any weeds 
  • Beds that can be reached easily from both sides, avoiding the need to tread on growing areas
  • Regularly hoe out any weeds, and Hoe in – rather than dig over – any green manures

Earthworms, bacteria and fungi, all of which contribute to healthy soil, can be adversely affected by disturbance such as digging and by compacting soil. Most soil life is closest to the surface, and digging can bring poorer quality soil to the surface. Digging can also help seeds from weeds to find ideal conditions for growth.


Protecting Fruit


There is precious little tree fruit this year after frost damaged blossom was followed by the dry summer which caused some fruit to fall prematurely. So, the last thing we want is for the birds to get to what little is left before we do. 

Fruit cages are a traditional form of protection for fruit trees and tall soft fruit plants such as blackcurrants, gooseberries and raspberries. A basic structure with removable is netting is ideal because it makes it easier to harvest the fruit and allows birds to feed on pests when fruits are not in season.

Low lying fruit, such as strawberries, can be protected by arcs of chicken wire supported by hoops. For large area, netting or chicken wire can be suspended slightly above the ground on a series of stakes.

Alternatively, birds can be deterred by scarecrows or similar devices. Birds are naturally afraid of birds of prey, and hawk-shaped objects can be suspended from masts. Pigeons are wary of reflective items such as CDs or metal tape can be tied to branches or canes, but these will need to be reconfigured periodically as the birds become familiar with them over time and lose their fear.

Keeping on Top of Weeds

During warm wet weather everything grows quickly - particularly weeds! In fact, because weeds have evolved to suit local climate and conditions they tend to outgrow whatever we may be trying to cultivate. Each square meter of soil can contain up to 100,000 weed seeds, all competing with our crops for water and nutrients, and providing a haven for slugs, snails and other pests.

The best natural ways to keep them at bay is to hoe regularly in dry weather, hand weed when the soil is moist, don’t allow them to seed, and to apply mulches to suppress growth. Light proof membranes can be used where you are not growing crops and, usually as a last resort, chemical weed killers are available.

The most common weeds are:

Bindweed – one of the most difficult weeds to overcome, it requires regular digging out destruction of every piece of root

Dandelion – remove flower heads before they seed and dig out the tap roots completely when the ground is soft (I’ve known them to grow and flower from just a root that I’d dug out!).

Bramble- highly invasive and can inflict nasty scratches. Dig out their roots completely

Goosegrass (‘sticky weed’) and Common chickweed – low growing weeds that are easily dug out by their roots.

How to keep on top of weeds...


Hoeing – hoeing takes the heads off weeds as soon as they break the surface - if beds need hand weeding then you’ve left it too late!. It’s good to hoe at least twice a month and weekly hoeing is even better. Choose a dry day if possible so that there is less moisture in the ground to allow the weeds to regenerate.

Stop digging – this made be counter-intuitive but digging can help dormant seeds within the soil to start germinating. The growing process is triggered when buried seeds are exposed to light, moisture and/or air.

Mulch – applying organic matter to the surface will bury and weeds or seeds and inhibit their development. It also allows the soil to retain moisture and nutrients allowing the intended fruit and vegetable crops to grow. 

Don’t let annual weeds set seeds. Dig out dandelions and other annual weeds before their seed-heads fully develop.


Success with Seeds

Most of us grow our plants from seed – it can be a challenge but it’s the cheapest and most rewarding method. The following tips can give your plants a head start and valuable extra days’ growth:

  • Clean any  containers and trays to remove any traces of pests/diseases
  • If you are sowing directly onto the plot, the soil temperature will need to be consistently above 7degC (usually early-mid May). Horticultural fleece or clear plastic      sheeting can help warm the ground sooner.
  • If you are planting in trays, put the compost in a warm place prior to planting
  • Space your seeds at the distances recommended on your seed packets

Large seeds that are wrinkled (e.g. peas and beans) can benefit from soaking prior to planting.





You can prepare for dry weather by:

Digging – breaking up the ground will help your crops develop deeper roots, providing them with access to soil that is cooler and moister. It can also help to incorporate organic matter into the soil.

Applying organic matter – compost and manure are excellent materials for retaining moisture (along with nutrients and beneficial bacteria).

Weeding – weeds need moisture to grow and so regular weeding will leave more moisture in the ground for the crops we want to grow.

Mulching – applying mulch after heavy rain or heavy water will slow down the rate at which the ground dries up (and has the added benefit of restricting weed growth).

Allotment Inspections

When we inspect the plots every month we’re doing it to ensure that they are in good order and being actively worked. We’re not looking for the perfect plot but one that is being used and is well maintained. After all, no one wants a plot next to one neglected and covered in weeds.

We start the inspection in March and finish in November. It is very noticeable that those people that winter dig or cover their plot are off to a flying start.

Your tenancy agreement explains the rules about how much of your plot must be cultivated and the structures and trees allowed on the plot. As site inspectors, we’re looking to see that the rules are followed in a sensible, practical way. Everyone has an off month, goes on holiday or has other calls on their time. However if after a few months there isn’t any activity, or very little work going on, then we’ll report it and you may get a letter. That’s why it helps us all that if you have a long term problem, you let you site representative know, as there may be help available. 

The golden rule is to have a productive plot that you’re pleased with, gives you pleasure and is one that makes you a good neighbour.


Helping Birds Through Winter


Birds are (generally) beneficial to vegetable growers. Here are some ideas for things that you can do to help birds survive the coming winter.

Throughout winter help to ensure that birds have access to food and water.

Leave a few seed heads on this year’s crops (this may also provide you with a generation of seeds to plant in the coming season.

Throughout winter, when the soil is hard, leave out any leftover fruit or berries for blackbirds and thrushes.

In addition to commercial bird feed, scraps of surplus food are ideal for birds: pastries; cooked potatoes; oats and grains; and grated cheese. 

Ensure any water supplies don’t ice over by floating a piece of cork or a plastic ball on the surface

Birds also need shelter and evergreens, such as holly and ivy, and beech offer protection during extreme weather. Birds start breeding from early spring so install bird boxes by February in a quiet, high position where they cannot easily be observed or attacked by cats. Trim back any trees/hedges before March so as not to disturb any natural nesting sites.   


Pruning Hard Fruit Trees

Always prune established apple and pear trees between November and February – when the weather is coldest the trees are dormant. Use sharp loppers/secateurs and ensure the blades are sharp and clean before making any cuts.

Pruning seeks to achieve three key objectives: to remove and dead, diseased or damaged wood; to remove overlapping or overcrowded branches, and; to boost the growth of buds for the year ahead. The key rules to follow are:

  • Remove branches which are growing inwards, towards the trunk.
  • Shorten long branches by 30-50%, and cut them at a ‘lateral’ – an outward growing side branch.
  • Make cuts at a slight downward angle (so that rain water drains off reducing the chances of rot.
  • Ensure cuts are clean by trimming any torn or ragged edges.
  • Cut out any new shoots from previous pruning cuts.

And work safely – wear gloves and take regular rests to help maintain concentrate, review progress and plan the next series of cuts.  


Crops that Grow in Pots


Growing vegetables in pots can be a good way to minimise weed growth and control plant growth. Pots also make a change from rows of crops providing visual interest to the plot.

Most types of soft fruit and vegetables will grow in plots. Salad leafs and onions, herbs, garlic, tomatoes, potatoes, strawberries, currents and chillies are often grown in pots, and potatoes can be grown in pots or potato bags. Carrots, beetroot and courgettes can also be successfully grown in pots, but seem to be less common (but for no good reason!). 

Whatever you decide to grow it’s best to use plants that have been produced to be smaller than usual - dwarf, compact or mini varieties. Some vegetables are not well suited to pots: brassicas; tall growing vegetables such as sweetcorn; and ‘thirsty’ crops.

The key rules are:

  • Use  pots that are big enough – generally diameters of 30cm or more produce the  best result
  • Plant in good quality compost – the plants have limited soil in which to grow so their soil should be full of nutrients 
  • Water regularly – the soil in pots dries out more quickly than those in the ground.  


The following container depths are suggested in Kay Sexton’s book (“Minding my Peas and Cucumbers”, 2011): 

  • 10cm (4”) – lettuce, radish, pak choi, welsh onions chives and other selected herbs
  • 15cm (6”) - dwarf beans, garlic, kohlrabi, small onions/shallots, dwarf peas, and some additional herbs
  • 30cm (12”) – aubergines, runner beans, beetroot, cabbage, chard, chillies, carrots, courgettes, cucumber, chicory, fennel, peppers, spinach, tomatoes, and turnips.