Roehampton Garden Society


September jobs on your allotment

  • Deep-dig out perennial weeds such as bindweed.  Keep weeding to prevent weeds seeding.
  • Begin to add well-rotted manure to bare areas.
  • Empty the compost bin by bagging up compost from the bottom of the bin or heap.  Store it ready for use next spring and start a new mix.
  • Spinach, coriander, rocket and parsley can all be sown until the middle of the month.
  • Sow fast-growing Oriental greens such as pak choi and mizuna.
  • Sow winter greens such as land cress, corn salad and hardy lettuce cultivars (including ‘Arctic King’ and ‘Valdor’) for spring picking. Sow kale for early spring harvesting and rocket for autumn harvesting.
  • Sow hardy annuals such as calendula officianalis in shallow drills for late spring flowering next year.
  • Sow green manures in vegetable beds that are to be left fallow for the winter.  When dug in they conserve nutrients and improve soil texture.
  • Sow broad bean varieties such as Aquadulce or Masterpiece Green Longpod in late September for harvesting in late May, early June.
  • Pot up strawberry runners to make new plants for next summer or plant out new strawberries.
  • Plant out spring cabbage.
  • Plant overwintering onion sets.
  • Plant daffodil bulbs for early spring flowering.
  • Start planting trees at the end of the month while the soil is still warm.
  • Harvest maincrop potatoes. Check each tuber for disease or damage and do not store damaged tubers. Store in a cool, dry place. Let the tubers dry off before storing in jute, hessian or paper bags in a dark frost-free place.
  • Store onions that have been dried in nets in well-ventilated conditions.
  • Continue to harvest sweetcorn.
  • Cut herbs for drying and use throughout the winter.
  • Continue picking autumn raspberries and blackberries.
  • Continue harvesting apples and pears. Store in a cool, well-ventilated place. Black, scabby blotches, distortion and cracking on apples and pears indicate scab disease. Affected fruit will not store well but can be eaten now.
  • Leave autumn squashes to ripen on the plant as long as possible. Place fruit on a wooden board or tile to prevent soiling.  Fruits are ready when richly coloured and ring hollow when tapped.
  • Protect leafy vegetable crops with bird netting.
  • Cut out the fruited canes of summer raspberries, blackberries, loganberries and tayberries. Leave the new green canes, as these will crop next year. Prune blackcurrants.  After picking autumn-fruiting raspberries, do not prune. Wait until late winter/ early spring to cut all the canes down to ground level.
  • Keep leeks protected with insect mesh against leek mining fly and leek moth.
  • Ensure carrots are protected with insect mesh as carrot flies are most damaging in late summer and autumn.
  • Water plants in the morning to help prevent fungal diseases.
  • Continue to feed and water tomatoes. Cropping can continue well into the autumn.
  • Clean the greenhouse to reduce overwintering pests.
  • In the greenhouse sow herbs, salad leaves such as pea shoots, beetroot and chard for winter leaves.
  • In ponds, thin out oxygenating and floating plants.  Leave debris at the side of the pond overnight so creatures can return to the water.
  • Apply grease bands to fruit trees at the end of the month to deter winter moth. (or try the new Fruit Tree Grease in the store)
  • Do not compost blight-affected foliage or tubers of potatoes and tomato plants. Do not add rose leaves affected with black spot to the compost heap.


August jobs on your allotment

  • Sow green manure crops such as mustard to dig in during autumn.
  • Sow oriental vegetables such as mizuna, pak choi and mustard greens for salad leaves- they bolt less at this time of year.
  • Sow parsley to last through till spring and basil on a sunny windowsill.
  • Sow Swiss chard and perpetual spinach at the beginning of the month.
  • Make a last sowing of beetroot at the beginning of the month.
  • Sow fast growing ‘catch crops’ for autumn use, such as radish, lettuce, rocket and turnips.
  • Plant out winter brassicas, broccoli, kale and cabbages in limed soil to reduce club root infestations.
  • Plant new strawberries now, either as detached runners or new plants.
  • In dry weather keep runner beans well-watered twice a week to aid setting.
  • To reduce risk of tomato blight, water directly onto the roots not the leaves.
  • Harvest sweet corn when a grain exudes milky juice when tested with a fingernail.
  • Harvest onions and shallots when the stems are dry and papery.
  • Start harvesting runner beans, parsnips and cucumbers as ready.
  • Complete harvesting of second early potatoes and begin to harvest main crop potatoes as they begin to flower.
  • Harvest early ripening apples and pears.
  • Summer prune trained fruit trees such as fans, espaliers and cordons.
  • Prune plum and damson trees after fruiting.
  • On grape vines shorten fruit bearing branches to two leaves beyond the fruit bunch.
  • Prune out fruited canes of summer raspberries.
  • Tie in new canes on raspberries and blackberries.
  • Keep protective insect mesh on carrots until autumn.
  • Cut back chives if showing signs of rust and new shoots will quickly appear. Remove mint plants showing signs of rust. The disease will persist over winter and re-infect new plants next year.
  • Pick off and destroy rosemary leaf beetle that are active at this time of year.
  • Divide clumps of chives.
  • In the greenhouse avoid splashing water onto leaves.  Moisture triggers spore germination of fungal diseases.


July jobs on your allotment

  • Hoe off weeds on bare soil, water well then cover with mulches to prevent moisture loss, for instance, pile grass clippings onto layers of newspaper.
  • Add material to compost heaps, mix greens (nitrogen rich) with browns (carbon rich) at 50/50 ratio.
  • Water heaps if dry and turn to speed up decomposition.
  • In early July continue to sow beetroot, chard, perennial spinach, kohl rabi and turnips for autumn harvesting.
  • Sow dwarf French beans.
  • Sow kale for early spring harvesting and rocket for autumn harvesting.
  • Sow beetroots Choggia or Burpees Golden for autumn eating.
  • Plant specially prepared potato tubers for Christmas crop.
  • Finish planting out leeks.
  • Remove the main shoot on cordon tomatoes where they hit the greenhouse roof, or a leaf or two above the seventh flower truss.
  • Water soft fruit and fruit trees during dry spells to encourage good fruit development.
  • Water courgettes consistently so they continue to flower and crop.
  • Mulch brassicas after rain to lock in moisture and nutrients and lessen the effect of club root.
  • Prune cherries and plums after fruiting.  Remove weak, damaged and crossing branches.
  • Pinch out climbing beans once they reach the top of supports.
  • Once harvesting of summer fruited raspberries is finished, cut old fruited canes to ground level and tie in new, healthy canes to supports.
  • Summer-prune red and white currants and gooseberries. For gooseberries trim back all side shoots to 3 or 4 buds from their point of growth and cut out shoots that cross into the middle f the bush.


June jobs on your allotment

June Foxgloves

  • Continue to hand-weed or hoe regularly to keep on top of weeds.
  • Dig deep to remove highly invasive bindweed as it appears.
  • Continue to mow or clip grass paths weekly.
  • If you have sown green manure, dig it in this month to fix the nitrogen in the soil.
  • Water potatoes well, for good-sized tubers and reduced problems with scab. (Remember to target-water, not spray, to avoid water wastage.)
  • First, second and salad potatoes may be ready for harvesting. Tubers should be ready when plants begin to flower.
  • Water tomatoes regularly and evenly. Uneven watering can cause cracked fruit and blossom end rot. Regularly pinch out side-shoots on cordon tomatoes and tie in plants to supports.
    Feed every 10-14 days with a liquid fertilizer, changing to a high potash fertilizer once the first fruits begin to set.
  • Plant out sweet corn 16” apart in blocks, not rows, to aid wind pollination.
  • Continue planting out or direct-sow runner and French beans.
  • Direct-sow courgettes.
  • Sow radicchio in drills for autumn salad leaves.
  • Sow fennel and oriental greens such as mizuna and pak choi.  June sowings reduce the risk of bolting.
  • Successionally, sow salads, rocket and basil etc every two to three weeks for continuous picking.
  • Make a late sowing of peas for an autumn crop.
  • Quick-germinating annuals, such as cosmos, that attract insect pollinators can still be sown.
    Sow wallflowers for next year.
  • Quick-maturing radishes or salad leaf crops can be sown between brassica rows. Ensure netting on brassicas is bird-proof.
  • Sow overwintering carrots such as Autumn King or Chantenay.  Cover with insect-proof mesh to prevent carrot root fly.
  • Transplant pencil-thick leeks now into 6” deep holes. Cover with insect-proof mesh to prevent leek moth damage.
  • Plant out pumpkins, squashes in well-manured ground. Plant out outdoor cucumbers and peppers. Protect with fleece on cold nights.
  • In the greenhouse ensure adequate shading.  Check nighttime temperatures and close door on cold nights.
    On hot days keep greenhouse temperatures down by using maximum ventilation and damp down greenhouse floors to increase humidity.
  • Keep fruit bushes well watered. (Target-water, not spray, to avoid water wastage.) Protect soft fruit from bird attack by netting securely and tie in new raspberry and blackberry canes.
  • Continue to check for sawfly larvae on gooseberries. Hand pick off.
  • On plum trees, after the ‘June drop’ of excess developing fruits, thin the fruits to prevent over laden branches breaking.
  • Continue to regularly harvest established asparagus – mid April to mid June. If asparagus growth is weak, apply a general fertilizer of fish, blood and bone.


May jobs on your allotment

Pea Frame

  • Hand weed and hoe regularly to keep on top of weeds. (Chickweed will produce 2,000 seeds per plant per season if left untouched!)
  • Keep the soil in good condition. Add garden compost or well-rotted manure to maintain soil structure and retain moisture and nutrients.
  • Sow fast-growing green manure where there are areas of bare soil where summer or autumn vegetables are to be planted out. Dug in before July it will fix nitrogen in the soil.
  • Plant comfrey.  The leaves can be used as a compost activator, as well as a making an excellent liquid feed.
  • Keep adding to the compost heap, making sure to mix ‘greens’ (lawn cuttings etc) with ‘browns’ (ripped cardboard, straw etc)
  • Continue to mow grass paths.
    • Strimmer is available to borrow in store. Charge £1.00.  Contact rgs.sw15@gmail.com to book.
    • Lawnmowers, free to borrow, are stored in the toilets on both sites.
  • Earth up potatoes when shoots are approx. 9 inches to prevent green tubers, pulling the earth up with a rake to form peaked rows. Remove any cold-damaged foliage.
  • Watch out for early summer dryness. Recently planted trees, shrubs and fruit need regular watering for the first two growing seasons.
  • Remove raspberry suckers encroaching onto paths or between rows.
  • Sow salad crops successionally, including radishes, spinach and beetroot and herbs such as basil, coriander and parsley.
  • Sow cauliflowers, sprouting broccoli, Brussels sprouts and leeks for harvesting next winter.
  • Sow sweet corn, French and runner beans direct into the soil.
  • Sow carrots.  Use insect mesh to protect from carrot fly.
  • Make late sowings of peas by the end of the month.
  • Prepare a fine seedbed and sow flowering annuals to attract pollinating insects.
  • Plant out tomatoes towards the end of the month watching out for drops in nighttime temperatures below 12 degrees C.  Be ready to put protection such as fleece or cloches around plants on cold nights.
  • Sow pumpkins, squashes and outdoor cucumbers under cover now or outdoors towards the end of the month. Watch for cold nights.
  • Start hardening off tender plants for planting out at the end of the month.
  • Ventilate greenhouses on warm days and cover vulnerable plants with fleece if cold nights are forecast. Apply shading to prevent scorching of plants.
  • Place straw under strawberries to keep fruit clean and deter slug damage. Feed with tomato fertiliser every week.
  • Support broad beans with string attached to stakes. Watch out for blackfly on broad beans and rub off or wash off with squirted water. Pinch off the tips with blackfly above the flowers and bury in the compost heap.
  • Net cherry trees against birds.
  • Harvest stems of established rhubarb when the stalk reaches 9-12 in. Pull (do not cut) stalks, taking no more than half at any one time.
  • Inspect gooseberries for signs of sawfly damage. Pick off by hand.
  • Start harvesting established asparagus.


April jobs on your allotment

April Plot

  • Draw up soil around the base of peas and broad beans to support them and increase the rooting area.
  • Plant early potatoes when chits are 2cms long.
  • Earth up early potatoes when they have made 8” growth.
  • Second early and maincrop potatoes should be sown by the end of the month.
  • Clean greenhouse glass to improve light levels.
  • On sunny days ventilate the green house by morning opening and close late afternoon to conserve the heat.
  • Avoid damping off in seedlings with good ventilation and not overwatering.
  • Make a late sowing of broad beans and sow early peas.
  • Make succession sowings of beetroot, Swiss chard, lettuce, radish, summer spinach, spring onions, parsnips and turnips.
  • Sow early varieties of carrot when the ground has warmed up.
  • Sow indoors or in the greenhouse Brussels sprouts, cabbage, early leeks, cucumbers, courgettes and peppers and sweet corn. Seeds available in store.
  • Once tomatoes have their first true leaves, plant them deeply into individual pots
  • Sow tomatoes for outdoors.
  • Water crops regularly in dry weather.
  • As weather warms make an early sowing of climbing or dwarf beans to transplant next month. Root-trainers available in the Store are ideal.
  • At the end of the month sow tender vegetables indoors, such as runner beans, squash and pumpkins.
  • Sow herbs, dill, fennel and parsley from seed.
  • Harvest rhubarb by pulling a few stalks at a time. Put the leaves on the compost heap.
  • Plant out autumn-sown sweet peas or direct sow outdoors.
  • Finish planting shallots. Available in store.
  • Plant soft-neck garlic.
  • Plant up new asparagus and globe artichoke beds.
  • The first cutting of asparagus is traditionally made after St George’s Day, 23rd April and the last cutting on the longest day, 22nd
  • Weed ‘defensively’; remove weeds before they flower to avoid seeding.
  • Cover radishes and turnips with horticultural fleece to protect against flea beetle.
  • Watch out for early aphid attacks. Quick action by manually removing these or hard- spraying with water can reduce likelihood of damaging infestations.
  • Feed roses with rose feed.
  • Once leaf buds open, start formative pruning of plum and cherry trees.
  • Use fleece to protect blossom of trees such as pears if frost is forecast.
  • Sow annuals to attract pollinating insects such as Nigella, single flowered marigolds, Comos, Caliphonian poppies, oregano and thyme.
  • Keep grass paths manageable by regular cutting.
    • A strimmer is available to borrow in the store. Charge £1.00. Email rgs.sw15@gmail.com to book.
    • Lawnmowers (fee to borrow) are stored in the toilets on both sites.


March jobs on your allotment

March primulas

  • Continue soil preparation by hoeing to suppress early weeds and cover with black landscape fabric/ weed suppressant or a thick layer of composted stable manure to warm the soil. Top- dress overwintering vegetables with a general fertilizer.
  • Apply a general fertilizer to all areas required for early crops.
  • To lessen the impact of brassica club root, raise the soil pH by adding lime to brassica beds. Some club root resistant varieties are available in store, g. Brussels sprouts Crispus, Cabbage Kilaton.
  • Sow outdoors early cultivars of beetroot, broad beans, peas, early cultivars of lettuce, radish, early spinach, parsnips and turnips. Seeds available in store.
  • Towards the end of the month early varieties of carrot can be sown. Sow indoors or in the greenhouse Brussels sprouts, cabbage, celery, celeriac, early leeks and tomatoes, cucumbers, courgettes, peppers and chillies. Seeds available in store.
  • Start herbs from seed. Sow dill, fennel, parsley and sorrel in plots to transplant later. Herb seeds available in store.
  • Watch out for signs of damping off in seedlings and be careful not to overwater.
  • Prune blueberries.
  • Direct plant shallots and onion sets.
  • By the end of March, if the weather is warming, plant first early potatoes when the shoots are 2cms long
  • Plant asparagus crowns.
  • Prepare trenches for runner beans with well-rotted manure and shredded paper at the base.
  • Clean greenhouse panes to maximise light levels.
  • Children can sow Candytuft, available in store.


February jobs on your allotment

  • Prepare for early vegetable crops by warming soil before sowing, covering seedbeds with polythene or cloches.
  • Keep off wet soils to avoid compaction. Use long boards as walkways, to spread your weight.
  • If the soil isn’t too wet, start to dig in overwintered green manures such as grazing rye and winter tares, as the frost should have killed them off.
  • Continue to tidy up and re-cut grass path edges where the grass has encroached on your plot.
  • Give your compost heap a ‘spring turn’ this month. Turning will aerate and stimulate the heap. If it’s too dry, continue adding wet kitchen waste, and water it occasionally. If too wet, add more carbon-rich stuff such as twigs, crumpled cardboard and paper waste, to open up and aerate the heap. Continue to add layers of uncomposted stable manure to your heap.
  • Empty compost heaps when ready and spread the well-rotted dark crumbly compost on beds prior to sowing or use as seed compost.
  • Chit potato tubers in a light, cool, frost- free place.
  • Clean pots and trays by scrubbing in hot, soapy water before starting to sow new seeds. Pests and diseases can overwinter in old potting compost, surviving to damage newly emerging seedlings.
  • Sow sweet peas in deep pots or Root-trainers in a cold frame, greenhouse or windowsill. (A wide range of sweet peas – single varieties such as King’s High Scent and Midnight as well as mixes e.g. Mammoth mixed and Incense are all available in store. Root trainers are available in store as well as free pots in the pot box next to the store.)
  • Pot on and pinch out autumn-sown sweet peas to encourage side-shoots to form.
  • Sow (Check out the range of varieties available in store such as Ildi, Megabyte F1, Gigantomo, Fandango,and Akron).
  • Sow sweet and chilli peppers from mid- February in a heated propagator or sunny windowsill. Chillies can be slow to germinate. (Check out the varieties available in store such as Long Red Marconi, Trinidad Perfume.)
  • Sow aubergines in a heated propagator or sunny windowsill. (Check out the varieties in store such as Black Beauty and Long Purple as well as the patio varieties Jackpot and Pinstripe.)
  • Sow celeriac in a heated propagator or sunny windowsill. (Variety, Prinz is available in store.)
  • Sow broad beans outside. (Check out the varieties in store such as Karmazyn, de Monica, Masterpiece Green Longpod and The Sutton.)
  • Sow cabbage. Check sowing advice on packets for different varieties. (Cabbage varieties available in store are Greyhound and Hispi.)
  • Sow peas outdoors. (Variety, Early Onward, is available in store.)
  • Sow onions and early leeks in the greenhouse or under cover. (Varieties, Blue Solaise, Below Zero F1 and Giant Winter are available in store.)
  • Sow early lettuce and keep in cold frame or greenhouse for earlier harvest. (Varieties Oakleaf Navara, Salad Bowl and Little Gem Cos are all available in store.)
  • Sow hardy annuals for companion planting such as Calendula and Tagetes indoors for earlier blooms.
  • Sow mustard and cress in a small seed tray on a warm windowsill for pickings in just a few weeks.
  • Complete pruning of apple and pear trees, gooseberries, redcurrants and prune out a quarter of blackcurrants’ older growth at ground level.
  • Prune autumn raspberries, cutting all canes down to the ground.
  • If summer-fruiting raspberries have grown above their supports, cut back to one or two buds above the top wire.
  • After pruning, apply a general-purpose fertilizer to tree, bush and cane fruit and mulch with well-rotted manure or garden compost. (all available in Store)
  • Top-dress all tree and soft fruit with sulphate of potash. (available in Store)
  • Spray dormant fruit trees and bushes with plant oil-based winter tree wash (available In Store) to kill overwintering eggs of aphid pests.
  • Apply 2” layer of well-rotted garden manure or garden compost around perennial crops such as Jerusalem artichokes or rhubarb. (Country Natural available in Store)
  • Start pruning bush roses at the end of the month.
  • Fruit bushes can still be planted now.
  • Force rhubarb for sweeter, earlier stems by covering crowns with straw and then a container to exclude light.
  • To reduce club root on brassicas, apply lime to soil at 270g per sq m, 8oz per sq yd. (lime available in Store)
  • Prepare a new asparagus bed by digging in well-rotted manure and order asparagus crowns.
  • Apply general fertilizers such as Growmore, (inorganic) or fish, blood and bone or seaweed, organic. (all available in Store)


January jobs on your allotment

  • As crops are harvested clear debris and cover cleared soil with weed suppressant.
  • Prune overgrown blackcurrant bushes- remove a third of the oldest stems to ground level.
  • Prune freestanding apples and pears, maintaining an open centre. Do not remove more than 20% of the crown in one winter
  • Sow broad beans (Karmazyn), aubergines (Black Beauty, Long Purple and Pinstripe), mixed spicy salad leaves or Mizuna and tomatoes (Akron is a new variety and remarkable for its high yields and sweet taste or Fandango which has good blight resistance) on windowsills
  • Sow lettuces, radishes, salad onions, and spinach on windowsills. (All seeds available in store) Grow on in greenhouse and plant out late Feb under fleece or cloches. (Fleece for sale in store)
  • Apply winter washes to fruit trees to control overwintering pests. (Winter wash available in store)
  • Prune gooseberries, redcurrants by removing dead wood and low-lying shoots. Shorten branch tips by one quarter, cutting to an outward facing bud.  Prune all side-shoots back to one to three buds from their bases.
  • Start ‘chitting’ tubers of early potatoes, Swift, second earlies, Pink Fir and Kestrel, in trays in a cool, light, frost-free location. Start chitting salad potatoes, Charlotte and main crop, Picasso as ready. (All varieties available in store from January)
  • Sow broad beans in pots under cover.
  • Sow winter salads in a greenhouse or windowsill.
  • Bring potted runners of strawberries under glass for forcing.
  • Sow sweet peas now and those sown in autumn can be potted on. Place on a sunny windowsill, in a cold frame or greenhouse. (Sweet peas available in store)
  • Pinch out tips of autumn grown sweet peas after four pairs of leaves have developed or at 3.5 cms.
  • Plan a crop system for vegetables- leaving a minimum of two years before replanting crops in the same place.
  • Open greenhouse vents on mild days.


December jobs on your allotment

  • Clear away any remaining plant debris from plots and compost if disease-free.
  • Earth up and check stakes on Brussels sprouts and other tall brassicas to prevent wind rock.
  • Prune grape vines before the end of the month, when dormant, to avoid sap bleeding.
  • Continue to plant fruit trees and bushes if soil is not frozen.
  • Divide and replant rhubarb.
  • Ventilate green houses on mild days to reduce diseases.
  • Plant blackcurrants 5cm below the soil to encourage new shoots.
  • Your last opportunities – 3 and 10 December – to shop for seeds in the Store for stocking fillers – sweet peas and herbs etc.
  • Protect autumn-sown broad beans with cloches during extended periods of frost.
  • For early tender stems, ‘force’ rhubarb by covering crowns with a dark-coloured bucket.
  • Plant fruit trees trained as cordons or espaliers to make good use of limited space. Check RGS website for guidance on permitted trees.
  • Plant blueberries in pots of ericaceous compost. (Ericaceous compost available in store)