Printable Allotment Sowing Guide

 Right, so here's a turn up for the books. I've actually beaten myself to something for once.

Regular readers will know that last week Sam, Iris and I stood over one very sorry-looking allotment , admitted defeat, and put it to bed early for the year. And regular readers will also know that about four days later the heavens opened and gave us more rain in two nights than we'd had all summer, because that's just how it goes round here. You wait, you moan, you give up, and then the sky finally does something about it. Typical.

But here's the silver lining. With one plot resting and the daily watering-and-picking routine on the other easing off a touch, I've actually had an afternoon or two spare before my shift starts, which doesn't happen often. So I've spent it doing something I usually mean to do every January and never quite manage: getting properly organised for the sowing year ahead.

Every year I tell myself I'll sit down with a cup of tea and a plan, and every year I end up scribbling dates on the back of a seed packet while stood in the greenhouse in my slippers. So this time, while the rain does the hard work for me, I've pulled together a proper printable sowing guide, the sort of thing I wish somebody had handed me thirty-odd years ago. It covers the main vegetables most of us grow up the plot, and a section for flowers too, because Iris would never forgive me if I left those out.

Print it off, stick it on the shed wall or the fridge, and hopefully it saves you the seed-packet-in-slippers routine I've been doing for years.

The Vegetable Patch (The Edible Stars)

Here's the veg rundown. A few of these I grow every single year without fail, and one or two of them (parsnips, I'm looking at you) I've had a strained relationship with that goes back decades.

Crop	Sow Indoors	Sow Outdoors	Harvest Time	Key Tips
Peas	Feb–Mar	Mar–Jun	Jun–Aug	Sow in old guttering, then slide the whole row into position without disturbing the roots.
Broad Beans	Feb	Mar–May (or Oct–Nov for an earlier crop)	Jun–Jul	Pinch out the growing tips once pods start forming, it keeps black fly away and speeds ripening.
Runner Beans	Apr–May	Late May–Jun	Jul–Sep	Keep them well watered once flowering starts, or the flowers drop before they've had a chance.
French Beans	Apr	Late May–Jun	Jul–Sep	Don't rush these into cold soil, they'll just sit there and sulk until it warms up.
Tomatoes	Feb–Mar	May–Jun (after hardening off)	Jul–Oct	Pinch out the side shoots on cordon varieties, and feed weekly once the first truss sets fruit.
Chillies & Peppers	Jan–Feb	Late May–Jun (or keep under glass)	Jul–Oct	Sow these earlier than feels sensible, they're painfully slow to get going.
Onions (from sets)	–	Mar–Apr (or Sep–Oct for overwintering)	Jul–Aug	Push them in firmly, birds love nothing more than yanking a loose set straight back out.
Garlic	–	Oct–Nov	Jun–Jul	Needs a proper cold snap to form good bulbs, so don't leave planting too late into a mild winter.
Potatoes	Chit Jan–Feb	Mar–May	Jun–Sep	Earth up regularly and keep an eye on the forecast, one late frost can undo weeks of work.
Carrots	–	Mar–Jul	Jun–Oct	Sow thinly rather than thinning later, it cuts down the smell that brings the carrot fly in.
Parsnips	–	Mar–May	Oct onwards	Use fresh seed every year and don't sow into cold, wet ground. I've killed more parsnips than I care to admit by ignoring this.
Beetroot	Mar–Apr (modules)	Apr–Jul	Jun–Sep	Each seed is really a little cluster, so thin to one seedling once they come up.
Courgettes	Apr–May	Late May–Jun	Jul–Sep	One plant is normally enough for an entire street. Two if you enjoy leaving them on neighbours' doorsteps.
Squash	Apr–May	Late May–Jun	Sep–Oct	Give them plenty of room to ramble, or grow them up something sturdy if space is tight.
Cucumbers	Apr	Late May–Jun	Jul–Sep	Keep the watering consistent, a dry spell followed by a soak is how you end up with bitter fruit.
Sweetcorn	Apr–May (modules)	Late May–Jun	Aug–Sep	Plant in blocks rather than a single long row, it makes all the difference to pollination.
Lettuce & Salad Leaves	Mar–Apr	Mar–Aug	6–8 weeks after sowing	Sow a short row little and often rather than a whole packet at once, or you'll drown in lettuce for a fortnight then have none.
Spring Onions	–	Mar–Aug	8–10 weeks after sowing	Brilliant for filling odd gaps between slower-growing crops.
Brassicas (Cabbage, Cauliflower, Broccoli)	Feb–Apr	Transplant May–Jun	Varies by variety, summer through to winter	Net them from the day they go in, the pigeons and cabbage whites will find them before you've had your tea.
Leeks	Feb–Apr	Transplant Jun	Oct onwards	Drop transplants into deep dibbed holes and just water in, don't backfill. That's what gives you the long white shanks.

The Bedding & Flower Border (For the Bees and the Eyes)

Iris runs this side of things more than I do these days, but here's what's worked for us.

Plant	Sow Indoors/Under Glass	Plant Outdoors	Flowering Time	Key Tips
Sweet Peas	Oct or Feb–Mar	May (after hardening off)	Jun–Sep	Pinch out the tips for bushier plants, and pick constantly, the more you cut the more they flower.
Sunflowers	Apr	May	Jul–Sep	Protect the seedlings from slugs early on, they'll strip a sunflower to nothing overnight.
Marigolds	Mar–Apr	May (after frost)	Jun–Oct	Plant near tomatoes to help keep pests down, and deadhead often for more blooms.
Nasturtiums	Apr	May	Jun–Oct	Grow them in poor soil if you want flowers rather than leaves, feeding them is counterproductive.
Pansies & Violas	Jun–Jul (for winter colour) or Feb–Mar	Sep or Apr	Nearly year-round depending on when sown	Sow in summer for flowers right through the darker months.
Lobelia	Feb–Mar	May	Jun–Oct	The seed is dust-fine, mix it with a little sand before sowing so it spreads evenly.
Petunias	Feb–Mar	Late May	Jun–Oct	Deadhead regularly, they'll keep going all summer if you stay on top of it.
Geraniums (Pelargoniums)	Jan–Mar	Jun	Jun–Oct	Need real heat to germinate, plug plants are far less hassle unless you've a heated propagator.
Cornflowers	Mar–Apr or Sep	Apr or Sep	Jun–Aug	An autumn sowing gives taller, earlier flowering plants than waiting until spring.
Poppies	–	Mar–May or Sep	Jun–Aug	Sow direct where they're to flower, they hate being moved once they've got going.
Cosmos	Mar–Apr	May	Jul–Oct	Deadhead regularly and they'll keep flowering right up until the first frost knocks them back.

Making It Printable

I've kept both tables simple on purpose, no fancy formatting, so they should print cleanly straight off the page. To get your copy: right-click anywhere on the guide and choose "Print", or use your browser's print function (Ctrl+P on a PC, Cmd+P on a Mac). It's laid out to fit comfortably across two sides of A4, so stick it on the fridge, tuck it in the shed, or laminate it if you're the organised sort, which, let's be honest, some of you clearly are and I clearly am not, most years.

A Word Before You Go

Now, a guide like this is only ever a starting point, mind. The weather won't read it, the slugs certainly won't, and somewhere along the way something will go sideways regardless of what the table says, because that's gardening. My courgettes gave up on me entirely a few weeks back despite doing everything by the book, and my parsnips have let me down more Aprils than I can count. Half of what you actually learn on an allotment comes from the years it goes wrong, not the years it goes right.

So use this as a nudge in the right direction rather than gospel, adjust it to your own plot, your own soil, and your own particular brand of bad luck, and don't be too hard on yourself when something doesn't come up. It happens to all of us, even after forty-odd years of doing this.

I'd love to know what's on your sowing list for next year, or which crop you've got your own grudge against. Mine's still parsnips.

Happy growing, everyone. See you on the plot.