Growing Tips

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). 



Plant Diversity



Growing many different types of plant close together creates several small natural ecosystems which, in turn, creates habitats for a wide range of creatures. This increases the chances of encouraging natural predators and helps to ensure that no single pest population is large enough to create problems.

Growing different plants together – companion planting – brings other benefits. For example, carrot flies are attracted by the smell of young carrot plants, but if strong-scented herbs or garlic/onions are growing amongst the carrots the carrot fly become confused.

A good approach is to plant some flowering plants between crops. Generally, these will attract hoverfly and ladybirds and occasionally bring further advantages – Cabbage White butterflies prefer to lay their eggs on Nasturtiums rather than cabbage plants, thus providing a natural decoy.

Other parts of the allotment can also support wildlife – log piles provide shelter predatory insects and compost heaps are ideal habitats for beetles and centipedes and provide a warm, safe haven for slow worms and hedgehogs.

Further information is available from the Br6thers web-site -

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:

and the all about allotments 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.


Managing the plot as you get older


The physical tasks around the allotment inevitably become more challenging as we get older. But there are things that we can do to help reduce the effort needed to maintain our plots.

  • Grow fewer varieties– cutting back on the number of types of crop you grow will reduce the effort required to prepare seedlings. Also, once crops are established, they will require watering, tending, etc. at the same time.
  • Plant low maintenance crops – Perennial crops (such as fruit trees, fruit bushes, and some herb varieties) will reduce the effort required to prepare seed beds each year. If you can’t get all of your planned crops planted in time, plant green manures to inhibit the spread of weeds and simplify the preparation of seed beds for the following season.
  • Grow in containers and raised beds – whilst raised beds take effort to construct, they are make it easier to plant, water and harvest crops. 
  • Get help from others - Family members, if available, are ideal but it may be possible to involve local schools, scout groups and other volunteers. 
  • Reduce the (effective) size of your plot –Covering part of your plot or growing through fabric will reduce the amount of time required for weeding. 

For more information see:

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.


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.


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.


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.