Sowing Plan for March 2018

When the ‘Beast from the East’ Siberian weather plunged us into deep midwinter, my February sowing plan collapsed. So the March sowing plan has been revised to take into account what didn’t get sown to plan in February. Also  long range weather forecast is for a colder than usual March.

Propagators in Greenhouse

Propagators in the Greenhouse

I’ve combined the first couple of weeks and will just plod through as I can. I’ve got a few other garden jobs to handle as soon as I can, not least repairing the storm damage to the shed door.

Wk 10 – 4th March / Wk 11 – 11th March Sowings

Greenhouse Tomatoes

Sow in small pots under heat (25ºC), thin to strongest and pot on when ready into 3” pots

  • Tomato Ailsa Craig
  • Tomato Black Russian


Ideal would be to start with bottom heat – around 20ºC – in modules if propagator space allows. (see best germination temperatures)

  • Cabbage Gunma
  • Cabbage Romanov Red
  • Cauliflower Igloo
  • Cauliflower Marvel 4 Seasons
  • Kale Mix


I’m trying a different method this year and starting them in individual deep modules, similar to root trainers. The ideal would be to start them at 15ºC but they’ll just have to go with what they get in the greenhouse.

  • Leek Blue de Solaise
  • Leek Winter Giant


Similar temperatures as leeks would be ideal for these but heated space is limited. I had decided not to sow these this year but I’d less Bedfordshire Campion seeds than I thought and looking at the onion bed, the autumn sown onions haven’t made it through the cold spell as well as I thought they would.

  • Onion Long Red of Florence, sow in modules to plant out outside when ready.

Spring onions to sow in modules to plant outside.

  • Spring Onion Guardsman
  • Onion N Holland Blood Red – note, these can be left to grow on and bulb up.


Start in modules ideally at 18 to 24ºC for planting out in the polytunnel

  • Lettuce Little Gem
  • Lettuce Tom Thumb
  • Lettuce Salanova

Legumes – Peas & Beans

Broad Beans Karmazyn – Soak for 2 hours in room temperature water then sow in pots in the greenhouse

Pea Meteor – Soak for 2 hours in room temperature water then sow in half-trays in greenhouse, once up plant out from trays in row.

Direct in the polytunnel

First early potatoes which I’d intended to plant a fortnight ago but even in the polytunnel temperatures were very low, dropping to minus 8ºC one night.

  • Potato Arran Pilot
  • Potato Home Guard

Carrots in raised beds

  • Carrot Early Nantes Pelleted
  • Carrot Touchon


  • Spring Onion White Lisbon
  • Onion Barletta (A small, fast white onion suitable for pickling after a couple of months or leaving to grow on to use as a salad or cooking onion)

Salad Leaves

  • Land cress

Wk 12 18th March Sowing

Brassicas in modules in the greenhouse

  • Brussels Sprouts Brigitte
  • Brussels Sprouts Early Half Tall
  • Cabbage Sarmash
  • Calabrese Marathon
  • Pak Choi

Wk 13 25th March Sowings

Tomatoes for growing outside, with additional shelter unless we have the summer we’re hoping for. Sow under heat in the propagator.

  • Tomato Incas
  • Tomato Red Alert
  • Tomato Heartbreaker

Spinach Perpetual – Sow in modules in Greenhouse

Direct sowing in the polytunnel

  • Corn Salad Vit
  • Spring Onion White Lisbon
  • Radish French Breakfast

Direct outdoor sowing – if weather permits.

Pea Kelvedon Wonder (pre-soaked)

Posted in Allotment Garden Diary
11 comments on “Sowing Plan for March 2018
  1. John.budde says:

    Hi. Been with your web site for a while, but have no allotment up and running yet. This year I will have an allotment ready for starting. It will be workable in the middle of March. So I if there is any advice you can give me, it would be helpful. I’m a total novice. Have very little knowledge in veg growing.

  2. Eric Doolan says:

    Hi John. Don’t think your March dates will suit me as i still have a lot of snow on my half acre garden.
    Will take your advice but a week later than you. Thanks Eric

    • John Harrison says:

      Hi Eric – very sensible. For a relatively small country we’ve a huge range of climate. The wet west and dry east, the warm south and less warm north – then there’s the London micro-climate which would be fabulous if only there was land and space!

  3. Ian Martin says:

    Hi John.

    Your article on sowing parsnips last month was most interesting as I have been growing my parsnips this way for a few years now because I was having difficulty growing them in the traditional way.
    I must point out to you that although they will grow to a good size you will always get parsnips with lots of root.
    As I don’t grow them for the show bench it’s not a problem for me because I do get a good crop.

    Ian Martin

  4. Debbie says:

    Hi John,
    I’m new to greenhouse growing, got a new GH late last summer so this year is my starting point.
    I have an electric tube heater installed and wondered would this be enough heat to start sowing now?
    I’m in North East uk, and its still quite cold here although the snow and ice has gone now.
    Any hints and tips would be greatly appreciated.

  5. Brian Morgan says:

    I’ve been sowing, parsnips, carrots and sweet peas into toilet roll inners for several years now. Being careful I find they work as well as peat pots or similar. I believe in fact they are better as they give a longer root run and rot away when you plant them in the garden

    Just an idea for using something that is normally thrown away


  6. Mary Geddes says:

    Toilet roll inners (and kitchen roll likewise) make a good contribution to the compost too!

  7. Graham Knight says:

    Hi John,

    I have been reading your sowing lists with interest and have been trying to figure a way of putting it all in one place. You mentioned last month that you put all your info onto a spreadsheet … is there any possibility you could share it to give us mere mortals a chance to try it?


    • John Harrison says:

      Hi Graham – I doubt it would make much sense to anyone but me as it is. Also, please keep in mind my sowing plan is based on where we are so your timings may well be different.
      If I get chance I’ll put something more presentable together for you. I’m a bit up to my neck in things at the moment.

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