I'm often asked what differences there are between growing on fixed beds like mine compared to the usual allotment row by row plan, in particular I'm asked about my use of block planting. (For the advantages of fixed beds and block planting Vs rows please read my article in last December's issue entitled "Fixed beds, rows and record keeping'.) In this piece I am going to deal with what I do in practice -bear in mind my parameters are to minimise work and that I'm growing in a very dry area; in a richer moister soil things might be different. Also I grow for only two reasons; for my own table and curiosity about how plants grow together.
The query that most commonly arises is what spacing to use if one is planting in blocks rather than rows -especially as seed packets only give row spacings. There is no doubt about spacing; the further plants are apart the better they do, indeed it's a salutary experiment to give just one plant an entire bed to see what it does! If you want bigger roots or more pods or cobs per plant then grow fewer plants better spaced out. (Though admittedly adding extra water will give very similar results in all drier regions.) If you want smaller vegetables then you can take them younger or grow them closer together. However if you go too far and cram them in too close then they choke each other and bolt or succumb to pests and diseases.
In general I find that the distances between plants in a row as suggested on seed packets is a better guide for block planting than the recommended distance between rows -which seems as often to be for ease of access as for any other reason. (Theoretically there has to be more space between taller crops to prevent them shading others and between hungry crops that rob their neighbours.) A further complication is the richness of the soil; in rich soil the plants grow vigorously and therefore deserve more air space so they do not choke each other, and in poor soil they need more root space so they can thrive at all. In other words more space is always preferable -if you want the biggest plants.
However I am not after large specimens. After all one has to carefully consider what one is after; a uniform stand of identical prize winning plants for the neighbours to judge or succulent baby vegetables for salads and stir frying. In many ways the prize crop is actually simpler to obtain and maintain than to provide oneself with regular daily supplies of fresh young crops throughout their season which is much more of a real challenge.
Though there are of course some crops that are of necessity grown in rows such as peas or some that get so big they fill the width of a bed such as courgettes and pumpkins. Admittedly peas can be grown up wigwams like runner beans or sown individually to grow up sticks, sunflowers or sweet corn. The leafless and shorter growing modern varieties designed for field culture can be grown in clumps or 'en masse' but then picking becomes more difficult. I sow peas in rows down the middle of my beds (which are aligned north-south) and then grow other crops in the partial shade on either side. I've tried double and triple rows but these just shade each other and make harvesting difficult.
Equally often I'm asked whether there are any crops (other than sweet corn) that are definitely better in a block arrangement. I do find that onions are more convenient when grown in a bed on their own as they need full exposure to the sun so that they ripen well. Even so I've had good results from those interplanted amongst strawberries (an unlikely companionship which surprisingly works well!) Likewise I do find haricot drying beans do best on their own as they also need full exposure to ripen well. Similarly I find a whole bed of early potatoes can be convenient for harvesting if it's alone whereas when planted with other crops this causes them root disturbance.
People also enquire how do I work a rotation when Icrops I grow crops with companions? As I said in the December article I rotate the most important (most readily infected or pest ridden) crops as the first priority. Thus potatoes and tomatoes, brassicas, onions and carrots are each all rotated over as long a period as possible never returning till four or more years have elapsed. Other crops that may be grown with them, such as broad beans with the maincrop potatoes, are rotated with them but if a conflict occurs I am prepared to allow these to return in fewer years.
For example I have not found it a problem when sweet corn was planted two years running on the same bed; this enabled me to make a bigger block of several beds. In a similar way I did allow running French beans that were on a sweet corn bed to be followed by a bed of drying beans the following year. Such minor aberrations although undesirable are not critical and by having such small hiccups I find it easier to fit in the most important crops to a longer rotation. Importantly it is not following any particular rotation that is crucial but to simply rotate all crops over as long a period as possible that counts.
I find some combinations work very well for me. For example a row of peas down the middle of a bed are planted on either side with rows of alternating blocks of beet and brassicas, or potatoes and sweet corn. (the latter only if low growing pea varieties are chosen and there is sweet corn on the beds beside, a bed of sweet corn needs two other beds to make a big block approximately fifteen feet each way.) Sweet corn is also grown with running French beans to climb up it and / or nasturtiums or squashes rambling underneath.
Maincrop potatoes usually have broad beans sown in the same planting holes to save labour and because the beans are cropped early to leave their excess nitrogen for the spuds. Likewise French beans (for the green bean) are usually alternated with over wintering brassicas for the same reason and because this seems to dramatically reduce the pests on the brassicas. Beets are alternated with brassicas in their blocks or rows as they are removed before the latter need all the space and the same goes for most of the salad plants.
Lettuces and salads are predominately grown in cells and transplanted out into any spare space with little heed to their own rotation as they have so few problems other than birds, slugs and drought. Indeed here in dry East Anglia the latter problem of drought is common most years so such crops as lettuce, spinach and salads are all happiest in amongst other crops than standing exposed to the wind and sun on their own.
I grow most plants in cells to transplant later as this frees the ground for longer and ensures plants survive where I want them as I find sowing direct is too open to the vagaries of nature. However for those crops that must be sown in situ I take exceptional care to ensure good germination and early protection from pests, weather and birds by using fleeces, cloches and plastic bottle cloches. These are removed as the plants grow but for the most bird enticing crops are immediately replaced by wire netting or similar. I find there is little point to do the job well to only have the birds scissor off the crop. Likewise all transplants are similarly protected during their first weeks outdoors, as well as being hardened off!
Many people who start fixed beds go straight to raised beds which is really jumping the gun. Most advantages come from the fixed beds, raising them adds complications with little advantage EXCEPT where the soil is shallow or has a high water table. Admittedly fixed beds end up raising themselves given time but this should not be accelerated until you are ready to cope. Raised beds dry out more quickly than fixed (an advantage for early sowing) and are harder for rain to soak in (it runs off), for mulches to stay on and they are thought to require sides.
I found, as I said in the December article, that all forms of edging to hold up the sides of raised beds were expensive and encouraged pests. I have no edgings allowing the soil to slump to it's natural slope at the edges and ends and maintain the whole of the middle of each bed as flat as achievable. (This even enables me to make the beds really level even though the ground slopes to the north!) I found that simply using the soil for the paths was cheapest and only required hoeing to keep the weeds down however it becomes untenable in the wet. Gravel or sand proved preferable but too expensive for my system of 40 beds which has over a thousand feet of paths; so I use straw.
Straw is easily obtainable here in Norfolk, and cheap if old straw is requested. It must be stacked for six months to comply with organic regulations and I prefer it partly decomposed anyway. Once put down thickly it is a clean pleasant path, excellent in the wet and does not encourage pests. It does not blow about once settled and is easy to rake off the beds if it accidentally gets on them. The major drawback is it needs topping up every year and it does slowly fill in the paths reducing the height advantage of my raised beds.
Every fourth year the potatoes come round in rotation so with them I take the opportunity of renewing the straw pathways. After the seed spuds are set the old rotten straw admixed with soil and worm droppings from four years of use is forked on top. I use fluffed up straw to further cover the spuds and renew the path at the same time. This no-dig method ensures that when I harvest the potatoes most of them are in the old rotten straw layer and come out remarkably clean whilst the fluffy straw keeps them well mulched and out of sight of the light so few turn green. (I also plant most of my main crop potatoes immediately I lift the crop which moves a lot of work from spring to autumn; a pleasanter and less busy time.)
Following the potatoes the soil is heavily enriched with all the rotten straw that has been applied and makes it ideal for sweet corn and /or brassicas (with a little lime added for the latter). These I find can then be followed, or mixed with, beets and or beans, and followed in turn by onions and then by roots and carrots which I find do not object at all to the undug firm soil left by the onions. Not that there is ever much dug soil save after the spuds as for two decades I have never done an autumn dig. Neither have I ever added any bought in fertiliser or muck; the fertility is home grown, and I don't even water except when sowing or planting -yet I still get wonderful crops.