by Sally Morgan
Traditionally, a legume crop is included in the rotation after a hungry crop, such as potatoes, to boost nitrogen levels. But the benefits to the next crop come only when the above-ground residues of the legumes, together with the roots and nodules, are dug into the soil and decompose. If you are growing the legumes as a crop, you will be removing a lot of the nitrogen when you harvest the peas and beans, so any benefits are surprisingly small. This is why a nitrogen-fixing green manure should always be included in your rotation.
Once the crops are harvested on my plot, the beds are sown with various green manures, which cover the soil over winter and for much of spring.
Here is an example of a 5-year rotation that makes good use of green manures to maintain fertility. As described below, green manures are integrated into the rotation at each stage of the cycle:
Year 1 Potatoes or sweetcorn
Year 2 Onions, leeks and garlic
Year 3 Brassicas
Year 4 Roots (carrots, beetroot) and legumes
Year 5 Clover
Here, the potatoes are cleared by autumn of the first year and the ground is sown with a rye and vetch mix. Sweetcorn can be undersown at the time of planting with low-growing trefoil or white clover, which remains through the winter. Any garlic and onions for overwintering can be planted in autumn too. Once the onions and garlic (or leeks) have been harvested, by autumn of the following year, a green manure of red or crimson clover can be sown, to remain until next spring when the brassicas are planted out. Any early brassicas can be followed by a summer green manure of crimson or red clover, buckwheat or phacelia, while the main-crop brassicas can be undersown with white clover. In year 4, carrots, beetroot and legumes are grown and, as they are harvested, the bed is sown with a mix of rye grass, clovers and vetches. This remains for 16 months until the next potatoes are planted. The year-4 legumes are undersown with white clover, which also remains through year 5.
PART TWO
GROWING PRODUCE
Chapter FOUR
The vegetable & flower garden
It’s surprising just how much can be grown in a small area, so there’s no need to devote a large part of your plot to vegetables. There will be plenty to do elsewhere on the plot! Nor do you have to limit yourself to annuals: try growing perennial vegetables, and some flowers for cutting.
The traditional UK allotment is 250m2 (around 300 square yards, or, in ‘old money’, 10 square rods, when the rod used to control a team of oxen was 5½ yards long). An allotment was deemed to be of sufficient area to feed a family of four for a year. You can fit 16 standard allotments into an acre! An acre – or even less – is still large enough to have plenty of space to rotate annual crops, grow some perennial crops, include some flowers and erect a greenhouse or polytunnel. That is a decent space!
The key to successful growing is to be able to take control of your plot and not feel that you are controlled by it. You need to be able to find time every week to keep on top of jobs: if you get behind for a few weeks, things will get badly out of control. It is far better to start with a smaller area and keep it looking good than to take on too much and get overwhelmed, so think carefully about the area you can realistically take on for annual crops.
In this chapter, I discuss planning your vegetable garden, weed control, companion planting and trying out perennial crops as opposed to annuals, plus sparing some space for flowers – not just for pleasure but also for other benefits. However, I am not giving detailed advice on growing specific crops, as there are plenty of other books that deal with this topic in depth: see Resources for some examples.
Visiting local allotments is a great way to get an idea of what crops to grow and how to arrange your plot. Every allotment on this site at Lytes Carey in Somerset has been laid out differently.
Planning your vegetable beds
What do you want to grow? The best place to start with a new plot is to make a wish list of all the vegetables you want to grow. Always choose crops you like to eat! I like to include unusual veg that I can’t buy in the supermarket. Also, try to choose those that grow well in your area, so talk to local growers or visit local allotments. Try not to grow too much, otherwise you’ll end up with a glut, although the pigs will always eat it! Successional sowing, i.e. sowing small amounts of seed every few weeks, will help to stagger the harvest so you can eat your produce at its best. Once you have your list, you can divide it into family groups and plan your crop rotation (see Chapter 3) and map out the growing area.
Bed size and style
In a traditional system, the whole of the vegetable area is cultivated, with dirt paths providing access between rows of crops. But more modern thinking is to opt for a bed width of 1.2-1.3m (4'-4'3") separated by paths, so you can reach across and never need to walk on the soil. Some prefer narrower beds, but remember that smaller beds mean proportionally more path, so more land is lost. The beds can be level with the ground or raised, in which case they are surrounded by a frame to contain the soil. Whatever size you opt for, standardize this through the growing area. This way, any cloches, fleeces and supporting systems that you buy will fit any bed.
The width of these raised bed is fine, but their long length may tempt you to take a short cut and step across the bed
Orientation
The best orientation for beds is north to south, to minimize the amount of shading, with, where possible, the taller plants growing to the shaded end of the beds (in the northern hemisphere this is the north end). Perennial plants tend to be larger and should be positioned in spaces where they are not going to shade the annual crops, so this is usually around the edges of the plot.
Planting patterns
Traditionally, vegetables were planted relatively close together in rows, which suited the seed drill, and guidance on seed packets still talks about rows. There are advantages to having long rows: they make sense if you use a seed drill, and if you are digging a potato or bean trench, for example, then it’s easier to have one long trench than four short ones. Many of the fleece and insect meshes come in relatively narrow widths, which suit rows rather than beds, and it’s easier to hoe a row.
But, increasingly, research shows that you can boost productivity by abandoning the row and opting for a more even distribution across the bed. An even spacing means that there is less competition between roots or shading from neighbouring plants, and the plants make better use of the nutrients. The result: more productivity. I find that it does take more time to hoe around plants in a staggered, equidistant planting pattern than in a row, but the crops also create a weed-suppressing cover more quickly, so there are fewer and smaller weeds. I prefer rows for onions, beetroot and carrots, because of the ease of sowing and hoeing, but for crops such as brassicas, squash, broad beans and sweetcorn I use a staggered pattern.
Onions planted in rows . . .
. . . and shallots in a staggered pattern.
How much space for staggered planting?
As a simple rule of thumb, take the recommended spacing for within and between rows and take an average. For example, if the packet says thin to 8cm (3") and allow 20cm (8") between rows, for an equidistant spacing you want (8 + 20)/2 = 14cm. (Or (3 + 8)/2 = 5½”.) If you want to grow small or baby vegetables, then you could opt for a closer planting, getting down to as many as 12 beetroot or carrot plants in a square foot (0.1m2).
Intercropping
Intercropping is the practice of making use of the empty space between crops when they are young by sowing or planting a quick-growing crop (also known as ‘catch crops’) – for example, growing radishes or lettuce between parsnips or brassicas. The main crop is slow to get established and will most likely have an erect habit and be widely spaced, as with leeks, brassicas, sweetcorn or peas. In contrast, the second crop is small and, because it is establishing while the main crop is still small, it is not shaded out. Good examples are lettuce, radishes, spring onions and beetroot grown for baby vegetables. Timing is critical with intercropping:
get it wrong and the second filler crop may compete with the main crop, reducing your yield. Inter-cropping will take up more nutrients from the soil, so the beds need to be well composted to maximize the yield of both crops.
This spinach is growing between broccoli plants, which will mature much later in the year.
Controlling weeds
I have met so many new allotment holders or smallholders who have cleared a load of beds, sown their seeds and disappeared off for a few weeks, only to return to find the beds covered in annual weeds. It’s a very depressing sight, and one that can easily put off the novice.
Weed control is critical, especially in late spring and early summer, when it seems that you are fighting a constant battle. If you can get through this stage it gets much easier, as the crops get larger and shade out the weeds, and the store of weed seeds at the surface of the soil has been exhausted. Persistent weeds such as thistles, docks, bindweed and ground elder need to be tackled firmly, otherwise the problem just gets bigger each year. If you are not sure of the identity of a weed, try downloading a weed app on to your smartphone, so you can look them up while on the plot.
For advice on clearing weeds and preparing the ground on an uncultivated or overgrown area of land, see Chapter 2, page 38.
Stale seedbeds
If you prepare your beds well, this will help reduce the number of weeds later in the season and save many hours of hand weeding. One way to do this is to create stale seedbeds. (This is particularly useful for growing carrots.) The soil is prepared to a fine tilth – the surface lumps broken up to a crumbly texture – and left for a couple of weeks. This allows the weed seeds in the soil to germinate, and you can then clear them with a hoe or a flame weeder, but remember to keep the hoeing shallow, as if you go too deep all you will do is bring new seeds to the surface. Then the soil is ready for sowing the seeds that you want to germinate!
Little and often
As many allotmenteers know, it is so frustrating to control the weeds on your own patch, only to see them creep in from neighbouring plots! I have received lots of advice regarding weeds over the years, but among the best is to carry a hoe around and take out the annual weeds as soon as they germinate. I have long used a push–pull hoe fitted with an extra-long handle so I don’t have to bend down. I now have two of them, one of which is left in the polytunnel so there is no excuse not to hoe the weeds when I go in to harvest.
Erect crops such as parsnips and carrots can soon get overwhelmed by weeds, so need regular hoeing.
Many years ago, a very experienced gardening friend told me to always return to the area where you last weeded, as it won’t take long to clear it before moving to a new patch. Using this method has helped me get some new areas under control in my walled garden. And, most importantly, don’t let weeds set seed, especially docks and thistles! The old adage ‘One year of seed equals seven years of weeds’ is so true. In our first smallholding, I decided that a patch of thistles should be left, as they attracted loads of pollinating insects. Big mistake! We battled thistles in that field for many years. Now we top our fields as soon as the flower heads appear, following the advice of Pauline Pears of what was then the Henry Doubleday Research Association, which was to leave the thistles until the middle of summer, when they were at their tallest and in flower, and then cut them to the ground to weaken them.
We carry a ‘jungle blade’ when we walk the dogs and chop off weeds as we go, and it’s surprising how much clearance can be done by just doing a little bit every day. In mid spring on my walks I focus on pulling out docks by hand, as the soil is moist and I can get the taproots out. My target of pulling 20 clumps a day has resulted in several fields being completely cleared of docks.
Weed barriers
Many annual seeds need light to germinate, so covering the ground with a mulch to prevent sunlight reaching the soil will stop many weed seeds germinating. Also, the mulch traps moisture, creating a microclimate that encourages root growth and helps transplants to establish. A mulch is simply a top dressing, and can take many forms. It can be a covering of straw, compost or bark, or sheeting of some sort.
A popular choice is the black woven groundcover fabric, which comes in different widths. It’s not cheap, but it lasts a number of years, and it is permeable – suppressing weeds while allowing water to pass through, so it’s a real time saver. You can lay the fabric over the ground and plant through it. We use it a lot, both on our paths and on larger beds where we know we won’t be able to control the weeds. For example, we use it to cover the pens cleared by the pigs as soon as the pigs are moved off.
You can get biodegradable mulch now, either paper or a plastic film. It is permeable and lasts about 16 weeks, slowly rotting down over the season and eventually disappearing altogether. Again, it is not a cheap option, but it does suppress the weeds and saves time.
A raised bed covered with biodegradable mulch that slowly breaks down over summer.
A ground cover also helps to stop mud splashing on to salad leaves.
Another option is the ‘living mulch’. This is a ground cover of plants growing under the main crop, for example a low-growing green manure such as white clover (see Chapter 3, page 62), or nasturtiums growing under brassicas. The living mulch suppresses the weeds while the main crop gets established. Care has to be taken with this option that the mulch does not grow too vigorously and compete with the crop plants.
These young brassica plants have been undersown with nasturtium, creating a living mulch to suppress weeds. It will remain once the crop has been harvested. The nasturtiums lure cabbage white butterflies away from the main crop.
Perennial vegetables
Perennial vegetables are a really useful addition to the plot. Some live a few years; others many decades. Some persist year-round while others die back in autumn and re-shoot in spring. Say ‘perennial vegetable’ and you probably think of artichokes and asparagus, but there are many more to choose from, offering a year-round supply of leaves, shoots, flowers, fruits or roots.
The advantages of growing perennial vegetables is that once they are established you don’t have to do much to keep the supply of edibles coming, other than a bit of weeding. Many provide tubers or leaves during the winter months, when other crops are in short supply. They don’t have to take up space in the vegetable beds, but can occupy those tricky spaces and corners. Some of the larger ones, such as artichokes and perennial kale, can be grown as barriers and hedges within the plot. Not only do perennials supply food, but they also enhance the plot in other ways, for example by attracting pollinating insects and providing a habitat for insect predators. Some are leguminous and will fix nitrogen, while others provide shade. They improve the soil too: unlike with annuals, there is no disturbance of the soil, and each year their root system gets larger, boosting the soil food web, while their fallen leaves add to the leaf litter and thus to the soil organic matter. Nutritionally they are better too, as their deep roots draw up nutrients from the subsoil in the same way as comfrey, as described in the last chapter (see page 57).
Some annual crops can actually be grown as perennials. In my polytunnel I have a Swiss chard plant that has been going strong for 3 years and now sports a huge woody stem. I don’t let the plant set seed. Instead, I cut it back in late spring, give it a good feed and let it recover to give me a supply of new leaves all winter. There is a vast range of perennials to choose from, and more are becoming available to the grower each year. In the table on the next few pages I describe some of the more commonly grown perennials, which I consider worthy of space in your plot.
This Swiss chard plant has been growing in my polytunnel for 3 years. It is cut back in spring to prevent flowering.
A selection of perennial vegetables
Common name(s) Latin name Characteristics and cultivation advice
Asparagus Asparagus officinalis Buy one-year-old crowns, dig a trench and backfill with compost. Then form a small mound along the trench and plant the crown
s so they sit on the mound, then backfill. Allow 70cm (28") between rows and 30cm (12") between plants. Let the crowns establish for a couple of years before harvesting. Don’t waste the space between the rows – plant them with other perennials such as chicory.
Babington’s leek Allium ampeloprasum var. babingtonii A wild leek with thin leek-like stems and a mild garlic-like flavour. It doesn’t set seed, so you need to plant bulbils in a sunny or part-shady position, and allow them to grow for a year before harvesting. The stems are cut at ground level in late autumn to winter and the underground bulb re-shoots in spring. It can reach up to 2m (6'6").
Buckler-leaf sorrel (French sorrel) Rumex scutatus A low-growing compact plant with shield-shaped leaves. Easy to establish from seed but it does spread readily! The young leaves have a sharp flavour and can be used in salads or wilted and used with meat and fish.
Cardoon (artichoke thistle) Cynara cardunculus This large thistle-like plant is actually related to the sunflower and was a firm favourite of the Victorians. Research has shown that the cardoon and globe artichoke are descended from the eastern wild cardoon; the Romans domesticated the globe artichoke, while the cardoon still resembles the wild plant. Cardoons are grown for their flowers, which attract bees. They are edible in part: the leaf stalks can be harvested in winter, blanched and used in gratins.