containers; growing medium and feeding; watering; what plants?; further help
You are growing for pleasure so grow what you’d like to eat, something unusual which is expensive or yo u can’t easily buy.
Look at the spaces you have available for growing and how much sunshine a day those spaces get. Look up as well as down.
If you have space on the ground you might prefer to grow some plants in containers to avoid large pests, bad soil, very dry shaded areas or just so that you can move your pots around with the sun through the year.
The information below can be used for growing in the ground, particularly if you have bad or compacted soil.
You can grow veg in almost any container as long as it is 15cm ( 6”) deep. Plant roots need a volume of soil so shape is less important than size. However, be aware that soil in a narrow or metal container will heat up quickly in the sun and this will stress your plants. So, as large as possible is the rule
– less watering and feeding needed.
Where can you grow your fruit and veg?
Limited sun (3 to 4 hours a day)
– most leafy veg will cope but most prefer more sun.
Try salad crops
– lettuce/ rocket/ coriander/ some oriental greens / mints/ lemon balm/ parsley/ chives/ chervil and sorrel(very good)/ chard/ leaf beet.
Blueberries/ redcurrants(very good) / blackcurrants/ alpine strawberries/morello cherry.
Raspberries (better in the ground).
Half a day’s sun (5 to 6 hours) – Peas/ beans/ beetroot/ carrots/ potatoes/ radish/ spring onion/ khol rabi/ fennel/ dill/ marjorams/ gooseberries/rhubarb; and for larger plants than in limited sun - chard/ leafbeet/ cabbages/ kales/ broccolis.
More than 6 hours
– Tomatoes/ peppers/ chillis/ aubergine/ courgette/ squash and pumpkins/ strawberries/ Mediterranean herbs
– rosemary/ lavender/ sage/ thyme/ origano/ tarragon/ most fruit trees and bushes.
The larger the fruit being produced the more heat that is needed. But do experiment, plants are very keen to grow e.g. Rather than tall vine (indeterminate) tomato plants with large fruit try bush
(determinate) cherry tomatoes in half a day’s sun – as long as they are warm and sheltered you will get some tomatoes even if you have to ripen them indoors in the autumn, and they do not need any pruning.
Indoors you can use a windowsill reflector made from a box and kitchen foil behind your crops to reflect light from behind and keep them upright rather than straining forward to the window.
Put pots on a table inside or outside to raise them out of the shadows.
Grow 2 or more crops a year - early veg grow before they are shaded by other plants.

How big is your container?
Check what it says on your seed packets for spacing plants.
15cm (6”) deep is OK for salad leaves/ small herbs/ small leafy veg, alpine strawberries/ pea shoots. Larger herbs such as sage/rosemary etc will be OK but will need more care and will not grow to full size.
30cm (12”) deep x 30cm minimum diameter is needed for a tomato, or pepper, chillis, carrots, beans. Of course can underplant with smaller herbs or greens – like basil with tomatoes.
This size pot will hold approx 15
– 20 litres growing medium.
40cm (15”) deep x 40/50cm diameter pot needed for squash, courgette, melon, fruit bushes and trees.
Beans need approx 2.5L growing medium for each plant, aubergine 10L, chard/leafbeet
4L, tomato 15L, pepper 5L, courgette needs approx 30L.
In open ground plants need less area of soil as their roots are able to go deeper looking for food and water.
What container?
Anything which holds a growing medium and allows water to drain out.
Water evaporates through terracotta or other porous materials. This keeps the roots cool but it will need more watering than a plastic or other non porous container where plants could get waterlogged and stressed. Choose pots to match your plants.
Poundshop sell a small hessian bag which you can hang on your washing line, wall hook or lay on the ground to grow a few herbs like mint/chives or lettuces, pea shoots.
A Lambeth recycling box is a good size for most vegetables.
Grow potatoes in a carrier bag; use old compost bags, or huge used builders bags from a builders merchant. If bags sag put a pole or floorboard vertically in each corner.
Tomato might be happier in a grow bag stood upright on its short end so the roots have more depth.
Old floorboards to make raised beds.
Grow small herbs, pea shoots, chives etc in a length of guttering.
Remember the larger the container the heavier i t’ll be to move around; If on a roof check weight of full containers and structural strength of your roof.
Secure window boxes and check where the water will be draining
– not staining your wall, use trays below if necessary.
Starting out try one large pot minimum 30cm deep x 30cm diameter if you have the space and try a variety of vegetables – leafy greens around a tomato; cut and come again lettuces or leafbeets/chards where you take a few leaves from each plant rather than waiting for each one to grow to full size
– plenty of seed companies sell mixed varieties of pretty lettuces specifically for this use.
In windowboxes grow small plants like short carrots and baby beetroots or root fennel to eat small or edible flowers (nasturtiums) or pea shoots, small trailing peas(asparagus pea).

You need spaces in your growing medium for roots, air, water and possibly worms if your pot is large enough. Organic matter holds water so adding to fine garden soil helps reduce water loss through over-fast drainage. It will also open up a compacted water holding soil allowing air and water through. Good for everything.
Use garden or bought compost, peat-free (Vital Earth, New Horizons, Fertile Fibre).
Garden compost = 1:1 green (garden and raw veg and fruit waste) and brown(stems, cardboard, woody twigs etc)) generally takes 1 year minimum.
Garden leaves collected into a well aerated bag for 2 years = leafmould.
Comfrey leaves (especially the Bocking 14 bred variety) make an excellent leafmould and miracle plant food.
Worm compost is very rich. DIY wormery in the kitchen? Japanese Bokashi method?
In open ground use the existing topsoil and improve it with compost or soil improver
(usually the woodier compost or compost with added nutrients or fibre).
In pots mix compost upto 1:1 with topsoil (crushed rock/organic matter called loam when bought sterilised in bags). Should always do this for long lived plants such as fruit bushes/trees which are kept health more easily in soil.
Water must be able to drain through – plants die if growing medium becomes compacted or waterlogged. A good idea to add perlite/vermiculite, grit or sharp sand
(not builders sand which may have lime in it and is too fine) in ratio 1:1:1 compost / topsoil/grit(or perlite/vermiculite). If have leafmould add that as well upto ratio1:1:1:1.
In smaller containers where don’t want heavier soil based medium use ratio 2:upto 1 compost/grit(or perlite/vermiculite). If have leafmould add that as well upto ratio 2:1:1.
The more grit the more drainage so adapt mix to your plants. Some bought composts may include grit.
Seeds and seedlings need a very fine, free-draining mix e.g. ratio 1:1:1 sieved compost/leafmould/grit (or perlite/vermiculite).
Plant food
In containers plants will need feeding after about 6 weeks.
Never be tempted to overfeed.
Fruiting plants like tomatoes, courgettes, aubergines, beans etc will need feeding wherever they are growing. Start feeding peas/beans when start flowering.
Start feeding tomatoes/squash/courgette when fruit start developing.
Nitrogen (N) e.g. garden compost/worm compost/chicken manure pellets/ blood, fish and bone/ liquid nettle feed/ seaweed meal. If overfeed
– leaves very green and grow at expense of the fruit. Leaves yellow if need N – but also if underwatered.
Phosphorus (P) needed for good root development. Garden compost/ bonemeal/ sewage. Rock phosphate is a finite resource. A lack of P can show, especially in brassicas as leathery, purplish leaves.
Potassium, also known as potash (K) needed for fruit development – use comfrey leafmould, comfrey liquid feed, woodash/garden compost (1:1).
Seaweed extract is a good general plant booster which provides some trace elements and promotes growth.

Comfrey or nettles – save leaves stuffed tightly into a plastic bottle turned upside down and bottom cut off. Add small amount of water and cover for a few weeks until very smelly and rotted. Drain off liquid and mix 1:10 with rainwater as plant food.
Can also use leaves of alkanet, a weed with brilliant dark blue flowers from the same family, but not so powerful as a feed.
To feed garden crops average 50L (wheelbarrowful) compost spread over 5sq.m ground in spring. Upto 1cm(half”) thick; or well rotted horse manure 50L to 10sq.m
Y ou shouldn’t have to throw away the growing medium
in containers every year unless the plants are diseased, so start with a good growing medium.
Large permanent containers with topsoil need compost adding annually in spring, if necessary removing some of the existing to make room.
Small containers need the growing medium to be taken out and mixed with some new medium each spring, removing roots, to a compost heap if possible.
Practice crop rotation if you can, to avoid diseases
–
1 st year – potatoes/tomatoes – prone to disease, and need the richest soil and feeding.
Also squash, courgette, melon, sweetcorn etc
– all the heavy feeding veg/fruit
2 nd year – peas/beans. Need less feeding than year 1 crops.
Also chard, leafbeets etc the larger leafy veg needing feeding to grow large
3 rd year – brassicas (cabbages, kales, broccolis, rocket and mustards, some oriental greens)- prone to disease, need less feeding than year 2 crops.
4 th year – root veg need less feeding than year 3 crops.
Other crops and flowers are grown where ever they fit.

Drainage
Make sure your containers have drainage holes, lift pots onto feet so water can drain out, or put broken pot bits, bits of polystyrene, corks etc in bottom of pot where water can collect below the soil and drain easily. Could then sit pot in a tray to collect the draining water.
If it’s standing on the ground you can cut the bottom off your container, or enlarge the drainage holes, so that the roots are free to get down into the ground to search for water.
Might occasionally want to use landscape fabric in your containers to keep the soil in whilst allowing the water through, to minimise staining to a sill or bench.
Losing water
Plants lose water not only through drainage down into the soil, but also through evaporation from leaves and from the soil, and from run-off when soil is compacted and water can’t easily get into the soil.
Losses by evaporation will dry approx 3mm depth of soil daily in summer, up to approx
5mm on a very hot day, so over 9 days a 30mm pot could be completely dry. Wind will increase the rate of evaporation.
When it does rain you need at least 1- 2mm of rain before it even starts to recharge dry soil.
Water retaining granules will help to reduce drying out in smaller pots.
Keep soil covered or shaded to reduce evaporation (see mulches below).
When to water
Water regularly. You want the roots to go down as far as possible.
Too much water
– too much leaf at expense of root or fruit, and plants may wilt and die.
Too little water - plants will wilt and die. Tomatoes will get blossom end rot (the ends of the fruit will turn brown and rot).
Too little water too often - the roots will come up to the surface following the water, making them more susceptible to drying out.
Shallow rooting plants whose roots go down approx 30
– 50cm (12”-16”) need the most frequent watering e.g. lettuces/ onions
Medium rooting veg 50 – 80cm (- 2’6”) like potatoes/brassicas/beans less frequently.
Deep rooting veg up to 120cm (4’) like tomatoes, cucumbers, sweetcorn least often.
In open ground these veg may send their roots further down searching for water.
Seeds and seedlings should be kept moist.
Tomatoes, sweetcorn, courgette, squash etc need regular watering once fruit start.
Potatoes, peas and beans need regular watering once flowers start to form.
Edible leaves should be regularly watered at all times. If not they will try to flower and leaves will go stringy and dry. This could be OK for coriander which has tasty seeds.
Roots and bulbs need regular but generally less frequent watering. At least every 2 weeks, to keep them moist and to avoid the roots splitting when they get watered after getting dried out.

Your preference when you water
Water am. So that the plants warm up during the day and are not left sitting in cold water overnight when they may not be drawing it in. Minimise attracting slugs and snails.
Water pm. To minimise evaporation.
All young plants need care until their roots are well down into the ground. In open ground try Jerusalem artichoke, globe artichoke or cardoons as well as fig or bay tree to beat a drought as they will survive without regular watering. Established plants of brassicas are also pretty tolerant. Most fruit and winter veg overwinter without watering.
How to water
Stick your finger into the soil and don’t water if it isn’t dry below the surface.
Need to keep soil surface loose so water can get in or water from below filling a saucer or tray. Can also use an upturned plastic bottle, lid loose and bottom cut off as a funnel stuck into the soil to direct water towards the roots.
Dry compost shrinks and is difficult to re wet. Small pots can be stood in a tray or sink for an hour to rehydrate, others will need to have holes dug into the surface to allow the water in without losing it around the shrunken edges of the soil.
If possible water seedlings from below and in shade to avoid burning, ideally standing the seed trays in water so that the fine compost is not compacted. If watering from above use watering can rose upside down to avoid flattening them.
Generally water the soil below the leaves to minimise waste and avoid wet leaves being burnt by sunshine. Keep soil moist not wet.
In open ground will need approx 8L (2 gallons) water per sq. m. as a general rule.
Water containers until water comes out of the bottom.
Once a week is a good general rule, although will be more often for small containers.
Check containers daily in mid summer - Tomatoes etc may need up to 4L a day.
Pray for rain.
What water?
Rainwater best
– collect in water butt, buckets. Can save cold boiled water from the kettle. Don’t use dirty washing up water on food plants.
Tap water clean and OK for seeds, seedlings.
Always using tap water on plants can lead to too much lime building up in the soil, one reason why you will need to mix new compost into pots each year.
Mulches
To reduce evaporation from the soil
– generally mulch in spring over wet soil and keep a space around plant stems. This is because the mulch is breaking down into fine compost, it will provide plant food but can harm plants in direct contact by being wet and/or by being hot as it breaks down:
On the ground and in large containers 100mmm (4”) thickness of chunky compost, or chipped bark, chipped woody branches, straw, or grass clippings on newspaper work well.

In smaller containers try cardboard around plants, carpet, or plastic sheet (although slugs like living underneath) - Ideally remove them temporarily if it’s about to rain or you are going to water the container. Can also use 23 cm (average 1”) leafmould added in spring or summer, or just add a small amount of compost.
Try groundcover between larger plants using small plants which won’t compete with your main crop, which will shade the soil and which might enjoy the shade from the larger plants
– use small herbs like thymes, alpine strawberries, salad cut and come again lettuces, spinaches etc, small beetroots and carrots, or flowers –marigolds, violets etc
Plant green manures over winter or when ground is unused – these plants are grown to cover the soil to avoid erosion, lock plant foods in and to become plant food when dug in. In small pots grow radish or lettuce
– quick growing small crops to avoid empty pots.
Anything to insulate the soil and keep the water in the soil.
If containers are overheating and losing water quickly can insulate them whilst on holiday by wrapping bubble wrap or newspapers around them when the pots are cool.
Self watering containers
Miracle boxes! Need much less frequent watering. Available commercially (Earthbox or
Stewart available in England)
Can DIY
– lots of www give details, can use 2 stacked storage boxes and a yogurt pot…. Basics as follows:
A container with a horizontal perforated screen about 125mm (5”) up from the bottom.
Just below the screen is an overflow hole through the container wall. The growing medium sits above the screen and the water below, fed by a vertical tube through the growing medium. Into a hole in the screen fit a pot, perforated or with slots all round it(like a pot for water plants), and sitting on the bottom of the container. Fill this pot with growing medium and fill the water reservoir, soaking the growing medium in the pot, before adding growing medium above the screen. Keep filling the water reservoir as the water is wicked up into the growing medium above. When it’s all moist start planting!
And mulch the surface.
Earthbox container approx 700 x 350 x 400h can allegedly grow 16 bean plants.

Use seed swops with friends or gardening clubs to share seeds/plants.
Start seeds in March and April for the summer. Don’t worry if you’re planting later than dates shown on the packets. If weather is cold and/or wet – wait. And London has a longer warmer growing season than most of the rest of the country.
Although I suggest some pot sizes
– experiment – eat plants young if they are going to outgrow your pot, and keep resowing through the year. A row of baby Florence fennel in a window box can look and smell lovely.
Try more unusual herbs – hyssop, bronze fennel, sweet cicely, summer savory, purslane….grow winter savory, a perennial, where thyme won’t grow easily.
Shallow pots in shade: chives, garlic chives, chervil as well as mints, lemon balm, coriander, rocket, sorrel, marjorams (anywhere).
In sun: basil(water from below, dislikes wet leaves), vietnamese coriander (lemon sherbet leaves, rampant if kept watered but may die overwinter), tarragon (in a dry space), fenugreek, coriander and fennel (tough).
In deeper pots min 30cm try lemon verbena (perennial, tangy lemon leaves), blackcurrant sage (perennial, blackcurrant leaves, bright red flowers), goji (superfood?), as well as lavenders, sages, rosemarys.
Vegetables and fruit:
In 15cm deep containers try spring onions, radish, Chanteney short carrots, pea-shoots, coloured cut and come again lettuces and leaf beets, landcress(peppery like watercress but easier), striped beetroots, strawberries, alpine strawberries, mini bush tomatoes, small chillis. Choose small varieties or eat them young.
Grow coriander, rocket, peashoots, mustard, alpine strawberries etc in a gutter…
Try trailing some mints, asparagus pea, alpine strawberries or small trailing cherry tomato with flowers in a hanging basket.
In 30cm deep pots try bush tomatoes yellow, red or striped, indeterminate (vine not bush) cherry tomatoes, French beans, peas, runner beans etc, asparagus pea (small, will trail or bush upwards, red flowers look good in a flowerbed), ‘Azur Blue’ khol rabi, chard – white stemmed and coloured, Florence and ordinary fennels, red orach (tall red stem with red, spinach like leaves), peppers, aubergine, small broccolis and cabbages, kale (try black kale - cavolo nero).
In 40 cm deep/dia pots try fruit trees, fruit bushes, rhubarb, fig and bay trees(tough and good in drought). Tomatoes, heritage potatoes, squash of all shapes, sizes and colours, courgette round as well as long, melon, mini sweetcorn.
Mix in flowers with edible seeds or petals – ‘pot’ marigold, poppies, violets, nasturtiums; or wild flowers….or flowers to attract insects and bees.
Garden Organic ideas for one 40cm dia/depth pot over one spring and summer - will need lots of attention and careful planting to keep pot full and looking good! a) 1 tomato, 12 peas, 8 lettuce, 4 rocket, 6 nasturtium or b) 5 french beans, 5 oriental leafs, 5 baby beet, 4 chervil, 1 golden thyme or c) 5 mini sweetcorn, 6 kohl rabi, 3 coriander, 3 parsley, 3 trailing tomatoes, 4 summer savory, 3 violets.
Maybe keep a couple of trays of seedlings, sown every few weeks, to regularly replace your small cut and come again veg and herbs(like rocket, coriander)so you always have something to eat.

Most of the above can be sown or planted outside in April.
Tomatoes, squash, peppers, courgette, sweetcorn, melon, chillis etc – all the heat lovers – need starting off indoors, but don’t panic, later is better than too early.
Lettuces, in particular, won’t germinate if nights are hot (over about 12C) so don’t bother planting in mid summer.
In May sow - broccoli, cabbages, celery, Florence fennel, french beans, peas, late potatoes, runner beans(indoors), sprouts, sweetcorn(indoors),
In June sow for a September produce show – beetroots, carrots, chards and leafbeets, kohl rabi, runner beans, salads, sweetcorn.
Also start to plant June onwards for autumn and winter.
Sowing to harvesting will be dependent on the weather. Approx : summer squash, courgette 8-10 weeks lettuce 6 weeks
French beans 7
– 13 weeks chard 10 weeks
Florence fennel 10 –15 weeks beetroot 12 weeks peas 13-14 weeks carrot 14 weeks sweetcorn 10-15 weeks runner beans 12-16 weeks melon 12-20 weeks winter squash and pumpkins 12-20 weeks aubergine 20 weeks chilli 24 weeks cardoon and globe artichoke 28-34 weeks
Help
The plants and information noted are not fully comprehensive or detailed. They are to get you started in the Spring.
The library has lots of useful books on growing food, and information is available from the following: www.gardenorganic.org.uk
www.mastergardeners.org.uk
www.verticalveg.org.uk
an ex Master Gardener with great info about container gardening. www.organiccatalogue.com seed catalogue, organic and non organic, good varieties and some plants as well.
www.seedsofitaly.co.uk
seed catalogue, lots in the packet and unusual varieties www.lambethhorticulturalsociety.org.uk
has interesting talks and a Trading Hut in West
Norwood with a good range of seeds for members
Blooming Stockwell gardening with Elaine Kramer on Wednesday afternoons at The Stockwell
Resource Centre Studley Road behind Stockwell tube station. A little oasis. www.rootsandshoots.org.uk
our local wildlife garden in Kennington, beautiful in late Spring, friendly and expert on organic gardening and also has the London beekeepers resident here.
Check opening hours. www.brockwellgreenhouses.org.uk
in Brockwell Park next to the lovely walled garden is full of unusual vegetables and fruit and friendly knowledgeable people. Check opening hours www.lambeth.gov.uk/greenchampion Sue Sheehan has lots of help, workshops and ideas for people wanting to lead a greener life. She knows where all the community gardening groups are in Lambeth.
Christine Flack
South London area Master Gardener chrisflack@phonecoop.coop