Grow your own Christmas dinner

Sow maincrop carrots by sprinkling seed sparingly into shallow drills of well-prepared soil. It's a good idea to cover the row with fleece to prevent carrot fly from reaching the seedlings.

Sow leeks in seed trays under cover. Sprinkle seed sparingly over dampened seed compost and cover with a thin layer of compost. Cover with a propagator lid or plastic bag until the seedlings emerge, and then keep the compost damp as the plants grow on.

Take sage and rosemary cuttings if you need to. Trim sprigs to 10cm, just below a leaf bud and push them into a pot of gritty compost. Water and keep compost just damp. They should root in six weeks on a warm windowsill.

Sow nasturtium direct in the soil or in pots. Large and small (cabbage) white caterpillars eat nasturtiums as well as brassica crops, so you can use the nasturtiums as a sacrificial crop to protect your brassicas, later in the year.

May

Thin carrots and parsnips by pulling the weaker and smaller seedlings to leave the largest growing, with 5cm between carrots and 10-15cm between parsnips. Where seedlings emerge in clumps, nip off unwanted ones at ground level to avoid disturbing those you're keeping.

Sow swede direct into shallow drills of dampened, well-prepared soil. Cover lightly with compost.

Sow Brussels sprouts, cabbages and kale into 5cm modules. Place on a windowsill or in a greenhouse to germinate.

Protect all young plants from slugs and snails, by leaving beer traps and conducting regular patrols at night.

Pot on sage and rosemary cuttings as new growth appears. Keep nasturtium seedlings well watered.

Check newly sown drills daily to ensure they remain damp. Keep on top of weeding to ensure weeds don't compete with your veg for water and nutrients.

June

Plant out leeks once they have reached the thickness of a chopstick, planting each one in a hole 15cm deep and 15-25cm apart. 'Puddle' them in by watering the planting hole rather than backfilling it with compost. This helps to reduce the amount of mud you have to clean out of the leeks when you come to prepare them for eating.

Plant out sage and rosemary plants after hardening them off. Choose the sunniest, most well-drained area of the garden, or grow in pots of free-draining compost.

Harden off cabbages, kale and Brussels sprouts over a 10-day period by taking them outside during the day and bringing them in at night, to adjust to outside temperatures. Then plant them out into rich, neutral to alkaline soil. Leave 45cm between cabbages and 60cm between Brussels sprouts and kale. Plant deeply and firm each plant in well.

Cover swede seedlings with fleece to ward off flea beetle.

Plant out nasturtiums if necessary, ideally beneath an obelisk or trellis frame, which they can climb up.

July

Fertilise your crops by lightly scattering fertiliser around each plant, or watering with a liquid feed. Organic fertilisers include fish, blood and bone, or you can make your own nettle or comfrey feed.

Make cabbage root fly collars, if necessary, by cutting 15cm circle of cardboard and snipping a slot into the centre. Place this around the stem of each brassica seedling, to prevent cabbage root flies from laying eggs in the roots.

Cover brassica plants with fine mesh to deter large and small white butterflies from laying eggs on the leaves. If you do find eggs on the leaves then snip the whole leaf off and attach it to a nasturtium leaf with a clothes peg. The caterpillars will eat the nasturtiums instead.

Draw soil over parsnip shoulders to prevent them from canker.

Keep watering carrots, parsnips and swedes if conditions are dry.

Check cabbages and kale for aphids. If infestations are small then ladybirds, lacewings and hoverflies will control them for you. If numbers reach pest proportions then blast with a jet from your hose or spray with a soap spray.

Varieties to try:

• Brussels sprout 'Trafalgar'
• Cabbage 'January King'
• Carrot 'Berlicum 2' (spring sowing) and 'Parmex' (autumn sowing)
• Kale 'Dwarf Green Curled'
• Leek 'Musselborough'
• Potato 'Carlingford'
• Parsnip 'Albion'
• Swede 'Brora'

August

Plant potatoes in sacks. Place two potatoes on 15cm of compost in each sack and add another 15cm compost. Water well and keep in a sunny, sheltered spot.

Keep inpecting brassica leaves for caterpillars or eggs, and transfer them all to your nasturtiums. Don't worry if your nasturtiums look worse for wear - that's what they're there for.

Earth up carrots to prevent the tops from going green.

Keep watering all plants regularly to ensure there are no checks in growth, or losses due to dry conditions.

September

Earth up potatoes by adding more compost (ideally mixed with manure) to the bag so only the top leaves are visible. Plant more potatoes in sacks, in case the first crop fails. Keep watering regularly.

To insure against loss, sow a late crop of carrots in containers of moist, sieved soil in the greenhouse.

Blanch leeks by slipping a collar over each and pulling earth around it, to promote long, white shanks. You can make the collars using cut pieces of plastic downpipe or cardboard. This is a fussy job, but worth it if you like long white leek shanks.

October

Stake Brussels sprouts and kale, as they can become top-heavy. Drive a sturdy stake into the ground and tie each plant into it.

Lift and store some of your carrots - you can leave maincrop carrots in the ground in most parts of the country but, as an insurance, lift some, twist off the foliage and store them in boxes of damp sand, so they're completely covered.

Bring potato sacks undercover, ideally into your greenhouse or indoors. This will protect them from frost and increase your chances of a good harvest.

November

When your Brussels sprouts have plenty of buttons, cut the tops of the plants off to stop upwards growth, which will ensure the plant's energy is directed to maturing the sprouts.

To insure against harvesting in heavy, frosty conditions, lift leeks now and pack them into pots of compost, to keep them fresh.

Mulch swedes and parsnips with a thick layer of straw to stop the ground freezing around them.

If conditions are mild, dig up your parsnips two weeks before Christmas and keep them in the fridge, as cold conditions increase sweetness.

Harvest carrots and swedes two days before the big day, gently loosening the soil and easing them out of the ground (or take carrots out of storage). Cut cabbages whole, leaving the stalks in the ground to resprout.

On Christmas Eve, harvest Brussels sprouts by cutting the whole stem, or selecting the biggest ones and popping them into a bag. Empty your sack of potatoes and select the biggest ones for the table.

On Christmas morning pick sage, rosemary and kale leaf by leaf.

For the best results, water and feed the plants as necesary, weed regularly to ensure there's no competition for light and nutrients, and remove pests on a daily basis.