Seasonal Articles

The Vegetable Garden in March

Planting potatoes in MarchThis March I am starting a new monthly update project which is centered more around what I’m doing in my garden. This is because it’s easier for me to write but also I hope you find it more engaging to see the garden grow over the season and follow me through my successes and some of the inevitable failures. It’s good for me too as it encourages me to expand my own horizons to keep you guys interested so hopefully we’ll learn a lot together.

march in the vegetable gardenI am hoping my gardening style may suit many of you guys as just like you I also have a busy life outside the garden. I am not a professional gardener with all day to mooch about between my rows but I do have to produce plenty of lush looking crops for photos and videos in the spare time I do have. I have set up my garden to grow organically while keeping maintenance to a minimum; I am hoping my methods will help you to do the same, to never see your garden as a chore and to enjoy the time you can spend there.

I would also ask you to bear in mind that I am growing in the North West of Ireland where Spring is slow to start. My sowing and planting times can be up to 4 weeks later than gardens in the South of England (you lucky blighters) so please adjust accordingly, i.e. for March read the February.

Vegetable garden plan

I figure the first thing we’re going to need is a little map as I have three very different parts to my garden; a small urban garden, a polytunnel and a large kitchen garden. I know I probably have a lot more growing space than a lot of you guys but the principles remain the same no matter the size of your plot. The three spaces are treated very differently; obviously the tunnel is a whole different climate but the other two also differ in the intensity of the planting. When planting my raised bed urban garden I am using varieties to help me squeeze the most out of a limited space whereas the large kitchen garden can be a little more lazy with larger crops and plenty of room to breathe.

You can see on the map my ‘urban’ garden is outside my back door so very handy for herbs, salads and other staples we use every day. The tunnel is on the way down to the kitchen garden and produces all the warm climate crops like tomatoes, peppers and cucumbers while the kitchen garden holds all the big stuff like cabbages and potatoes as well as root crops like carrots, parsnips and turnip. The idea is every month I will bring you through each section and we can look at what I’m doing, I’ll explain what I’m planting and why while looking at the common pitfalls I am trying to avoid. OK? Great, let’s get going.

Square foot timber raised garden‘Urban’ Raised Bed Garden
You may have seen this garden in our ground breaking video of the same title when we built it last year. While I obviously don’t live in the city the idea was to use a space similar to that which might be available in a city garden. The design consists of a ‘U’ shape layout backed with 6ft posts for climbing crops and a two tiered layout for plants of different root depths. I had also planned the bed with the ‘Square Foot Garden’ system in mind to trial the closer spacings recommended and to build a simple and easy to follow step by step system.

square foot raised bed vegetable garden

In March I still have some perpetual spinach, chard and beetroot in the bed along with a few straggler carrots and some strawberry plants. The beds only went in last year (2015) and are filled with a mixture of topsoil and ‘Envirogrind’ which did pretty well last year but still have room for improvement. I will be adding a layer of well rotted farmyard manure both to add organic matter to the soil but also as an inoculant to add important beneficial bacteria. I am lucky to have a supply of the excellent manure nearby (thank you Clive!) but if you don’t you can use a good bagged product like organic ‘Gee Up’ horse manure.

Rootgrow mycorrhzal fungiThe other thing I want to add, and this is because it is ‘new’ soil, is mycorrhizal fungi as I want to build up their beneficial networks quickly to help feed and water my plants. Mycorrhizal fungi grow hyphae (fungal ‘roots’) which transport water and minerals to plant roots in return for carbohydrates provided by the plant. Nearly 90% of plants have symbiotic (they both benefit) relationships with fungi so it makes sense to add them to new raised beds and potting mixes. The best way to add the fungi is to dip seedling transplants in a mycorrhizal powder when planting out, I think you will be surprised at how lush and healthy growth will be.

Adding compost to vegetable bedsWhen adding my soil amendments to my urban garden (and my main garden) I add them to the surface rather than dig in to avoid damaging these fungal networks; this is the idea behind ‘No Dig’ gardening where the soil is disturbed as little as possible. There is another advantage in not digging in manure when growing root crops like carrots as the roots will grow without forking (growing like a knarled tree) but more of this later when I’m actually sowing the carrot seed.

Square foot garden plan – Last year the urban garden had a square foot garden plan which needs to be rotated (shuffled around) to ensure crops of the same family aren’t growing in the same space. I will show you the finished plan in the April update when hopefully we can start getting some plants in the ground.

Tomato plants in a polytunnelThe Polytunnel
I am going to be honest here and admit I don’t use the polytunnel to its full potential and only produce tomatoes, peppers, cucumbers and squash as well as a few salads. I just use it for warm climate crops in other words and don’t use it to extend my season for a broader range of crops. That is all about to change now as I have you lot following me around, let’s see just how much we can get out of a modest tunnel and if the claims of ‘year round growing’ are really true.

At the moment I have a few salads and herbs in the tunnel but let’s take it we are starting with nothing. Like my other beds I want to feed up the soil with plenty of manure and will also be adding mycorrhizal fungi not because the soil in the tunnel is new but because I let it dry out completely over the Winter. I shouldn’t have done this as it is bad for the soil (I let it happen last year too!); even if you have nothing in your tunnel you should keep the soil moist.

Water polytunnelThis brings me neatly to the next tunnel job. I need to properly irrigate the soil before planting as the deeper layers will be dry and will be very difficult to water properly once planted up. The method here is to dig holes a foot deep around the tunnel and fill them every time I pass. Once the holes stop emptying quickly you can assume the deep soil has been properly soaked.

This year I will be replacing the plastic on the tunnel because it has become a bit tatty and cloudy over the 6 years it has been up. If your tunnel plastic is OK it is still well worth cleaning the inside and outside as you need the most light you can get and a dirty tunnel will cast a surprising amount of shade. I clean the inside with ‘Citrox’ which is also a natural disinfectant so also helps keep my tunnel disease free.

vegetable seedling plants in large polytunnelPropagation (sowing seeds in trays and pots) – As it is still too cold for nearly all outside sowing the polytunnel is where all the action is at this time of year. I actually use our large commercial tunnel to do the propagation for my garden but this is only because we have everything set up already so don’t be put off by the size in the photos. This month I will be sowing a broad range of crops in modular seed trays and pots; remember it is often still too cold to sow in the soil in your tunnel at this time of year, you should wait until your soil temperature is about 8ºC.

Modular seed traysMany of the crops I will sow will be destined for the kitchen or urban garden when the weather warms up; the reason I am sowing indoors now is I will be about a month ahead with 4-6 week old plants when ordinarily I would only be starting from seed. The head start you achieve gives you earlier harvests and enables you to get more from your garden over the course of the year. Growing in trays and pots later in the year is also very handy as when you harvest a crop you have new plants to fill the space and get growing straight away.

This March I am sowing for tunnel production tomatoes French beans, courgettes, basil, cucumbers, melons (a new one for me) and peppers. I will also be sowing a range of salad leaves including lettuce and Oriental salads like rocket and leaf mustard.

Vitopod heated propagatorMost of the seeds will be grown in pots with the exception of the very hardy Oriental salads which will happily germinate and grow in colder soil. The warm climate crops (anything which will have to remain in the tunnel) will need to be sown in a heated propagator or on a heat mat with a cover to reach the temperature required for germination (24ºC) and to protect the new seedlings from the cold. You will need to turn the temperature of the propagator down to approx 10ºC once the seedlings are above ground to stop them getting leggy due to too much heat and not enough light.

I will be sowing for outdoor production leeks, early cabbage, brussels sprouts, broccoli, early cauliflower, spring onions, kale, celery, celeriac, beetroot, kohl rabi and early peas in a propagator. The difference with these guys is as soon as they have germinated they should be removed from the heat and placed off the ground (I use an old wooden shipping pallet) and covered with fleece to protect them from frost at night.

You can read more detail about propagating vegetable seedlings by clicking the link.

Raised beds made of planks and timber postsKitchen Garden
As I mentioned in the intro I have designed my kitchen garden to be low on maintenance so it is split into separate raised beds with gravel paths between each bed. I use some of our standard raised beds in one quarter of the garden, the rest is made up of simple shoring made up of planks and timber pegs. I have also made my large beds 1.5m wide so I can exactly fit a ‘Growgrid’ planting mat or a 1.5m wide roll of mypex if I want to cover a bed to protect it and keep weeds down between crops.

Making a Plan
I don’t have much to do with the soil in March because I made most of my additions in the Autumn when I layered Envirogrind, manure and seaweed on the beds. I think I mentioned it at the time but this is where a proper plan is invaluable as different crops will have different requirements. Some of my beds will have a layer of manure (brassicas) while some won’t (carrots), I made my plan in the Autumn when feeding the soil so I have everything pretty much ready to go at planting time.

Quickcrop vegetable garden plan

If you haven’t fed your soil yet now is the time to do it. As you know I believe digging is best kept to a minimum so I would advise adding your soil amendments to the surface of the soil. This makes sense in March anyway as digging frozen or waterlogged ground is definitely a bad idea because it damages the structure of the soil. We can supply ‘Envirogrind’ which is a great all purpose soil improver, organic manure and seaweed and manure pellets all of which can be added now. Depending on your soil type (acid/alkaline or sand/clay) you might need to add other amendments like calcified seaweed or ground limestone but that is a whole article in itself, I will cover that next week.

Seed garlic for plantingGarlic – March is the last date you can plant garlic cloves as they need a period of cold for the clove to split and form a bulb. Cloves planted now will not yield competition size bulbs but they are still a very worthwhile crop especially as they don’t take up much room. I have garlic in already which I planted in late Autumn but I will add some extra as an experiment to judge the difference in size. Garlic will like Envirogrind raked into the surface of the soil and will also like potash, if you have an open fire and burn wood the ash will be ideal raked in with the Envirogrind.

Growing currantsBare root fruit – I have a number of fruit bushes dotted around the garden including black, red and white currants, cooking and dessert gooseberries, raspberries, blueberries and strawberries. These plants are an absolute joy when they are in fruit and take very little looking after so I will definitely be planting more. I haven’t added many of the hybrid berries yet (usually a blackberry cross) because I need to build some extra supports but I will be making up for lost time this season.

Hybrid berries include Tayberries, Tummelberries, Loganberries and Boysenberries; they all have the same growth habit as a bramble so need to be trained along wires. The fruits are like large raspberries with a darker colour ranging from vermilion to deep purple, usually with a more tart flavour. To be fair I haven’t actually put them in yet but will take some photos when I do and let you know how I got on.

Planting seed potatoes in a drillPlanting Potatoes – Normally I have one quarter of my kitchen garden under potatoes all planted in one block. This year I have spread the potato beds throughout the garden (you can see them in the plan above) in an experiment to see if it reduces the spread of blight. I am hoping that as the potato beds are not beside each other I should find it easier to manage any attack of blight I do get.

As you may know Bordeaux mixture (the organic method of dealing with blight) isn’t available any more so spraying isn’t really an option. You can make your own mixture using bluestone available from veterinary suppliers (I think it’s used on horses hooves) but there is a concern with the active ingredient, copper sulphate, building up in the soil so personally I’m going to give it a miss.

Chitting potatoes in egg boxEarly potatoes are planted mid March and are usually harvested before blight hits (especially if you have chitted them) so are rarely a problem. Chitting means leaving the seed potatoes in a cool, bright spot for a few weeks to encourage them to sprout, this brings forward the harvest date.

Maincrop potatoes are put in at the beginning of April so you don’t need to worry about them yet. I grow blight resistant varieties like Sarpo Mira, Sarpo Axona, Orla and Setanta so I don’t have to spray. Bear in mind that blight resistant varieties will eventually get blight but they will hold out much longer, usually until the tubers have reached a decent size. You can manage blight by removing any affected leaves and stems (and hopefully by spacing them out….) until you loose the battle and finally cut all the foliage down. I have been using this method for years and never spray but always get a good crop.

broad bean plantsSowing Broad Beans – Broad beans are hardy plants which can be sown in early March. It is beneficial getting them in early as it ensures the beans have developed well before they get the disease ‘chocolate spot’ later in the season which is very likely. Remember there are Autumn and Spring sown varieties of broad bean, the one we recommend for Spring sowing is the very reliable Witkeim Manita.

When sowing broad beans (15cm between plants, 45 cm between rows) it is worth building your support cage by pushing stakes into the ground and making a twine fence around the rows like a boxing ring. The plants are liable to wind damage when they get tall so save yourself the heartache later on and do it now.

Planting Onion and Shallot Sets – You can also put in your onion and shallot sets in March with the middle of the month usually recommended. I have found due to the odd weather patterns we have been having lately that you are better delaying to the end of the month or even into April. The reason for this is that onions are biennials (they have a 2 year lifecycle) and they can be prone to bolting when a cold Spring follows a warm Winter. They bolt because they think they have just been through another season if it gets cold in March, it is what happened last year and we have already had the warm Winter so…….

Planting onion sets in a Growgrid planting matI use the aforementioned ‘Growgrid’ planting mats for my onions as they cut out most of the weeding giving me one less headache. The mats consist of a weed barrier membrane with heat sealed planting holes at various different spacings, I use mat ‘D’ for onions which has a spacing of 15cm all round and find it perfect.

Onions also like ‘Envirogrind’ (what doesn’t says you), they also like to be well fed but be careful with manure as too much nitrogen can cause too much leafy growth and ‘thick neck’. Thick neck gives the onion a fat, soft neck where the stem joins the onion which is liable to rot and won’t store well.

Jerusalem artichokes – You can also plant Jerusalem Artichokes in March but I won’t be bothering because I don’t like them much and they are a nightmare to get rid of. If you want to have a go they grow like weeds, just stick them in the ground ,they will grow whatever you do to them!

  1. Derek Chapman

    I love the newsletters and read them avidly although I have not had the opportunity to grow too many veggies or potatoes as up till very recently I have kept cats. These chaps are all gone for now and so I am determined to add to my gardening experience. So far I have had great success with your herbs and tomatoes and I will be getting some more of those as the year progresses. But my query for now is in relation to broad beans as I see now is sowing season for them. I am passionate about broad beans but I never seem to be able to find a regular supply of them, in veggie shops or markets. So I want, if possible, to try planting them in pots, the size that I successfully grew the tomatoes in, 24 cm regular plastic pots. (It will take me the summer to switch a raised bed from flowers to veg.) Is this a feasible proposition, do you think? Please advise and I will purchase your Witkeim Manitas forthwith.

    1. Andrew

      Hi Derek
      Thank you for your kind comment. Broad beans are not traditionally grown in pots but that does not mean they are unsuitable. I would think a 24cm pot would be fine, just make sure you don’t let them dry out. I would also only grow one plant per pot with a good quality compost.

  2. Vanessa Sweeney

    Hi Andrew
    I think you should write a book……..your style is such a lovely readable mixture of good gardening tips and good humour!

    1. Andrew

      Hi Vanessa
      Thank you for your very kind comment. Yes, I would love to put something together in book form but I guess it’s a big step from writing blog articles to doing a proper book? Thanks again Vanessa, you never know……

  3. Dara

    Hi Andrew,
    I received 5 nice hessian sacks with the envirogrind that was delivered today, thank you very much for that! I’m building a greenhouse at the moment & just completed my first raised bed, so I’m looking forward to growing veg this year for the first time. Regarding the hessian sacks, is it possible to grow early potatoes in these? I’m keeping the greenhouse for tomatoes, chills etc & the raised bed for garlic & onions, so I’m limited for growing space until I tackle another raised bed probably next year.
    Regards Dara.

    1. Andrew

      Hi Dara
      Thanks for getting in touch. The hessian sacks won’t be suitable for growing potatoes in as they will dry out too quickly because of the open weave of the sack. If you want to use them because they look nice use the plastic sack the Envirogrind came in as a liner, just make a few holes in the bottom to allow them to drain. I hope this helps.

    1. Andrew

      Hi Mary, thank you for your kind words, I am really touched you like the articles. I am seriously considering a book if I can find the time to do it, I would love to compile my garden experiences into a more comprehensive collection even if I am the only one who ever reads it! Thanks again and thanks for reading.

  4. Anne Greene

    Hi Andrew,
    Have read through your blog which is great and very helpful in starting the new growing year. I have just one question for you – I have recently bought two Grape plants and have planted them in my borders in the greenhouse. Any help you can give me regarding same, I would be most appreciative of, especially with training and feeding. I’m determined to get these growing to fruition. Thanks
    PS I will certainly be after your 84 cell seedling tray for next year. I have all my seeds for this year.

    1. Andrew

      Hi Anne

      I will compile an article on grapes which I hope will help. For the first year you will be concentrating on growing the main stem up a vertical cane. Tie the main stem to an upright cane or pole while attaching lateral wires between the poles to train vines on to. The wires should be 1 1/2 foot from the ground with spacings of a foot between the wires, 3 should be enough. If you haven’t done so already cut back all side shoots to one bud from the main stem. I will get an article written asap.

  5. Therese Ellard

    Good website Andrew,
    I too am in the nw Ireland and have my first polytunnel with raised beds. I have filled them with envirogrind as the soil is very poor here.
    Is it going to be too ‘hot’ to grow in this year do you think? The beds were filled last week.

    1. Andrew

      Hi Therese
      You will be fine to grow this year, Envirogrind is a slow release soil improver and is not high enough in nitrogen to cause a problem. Can I ask if the beds are filled with Envirogrind only or mixed with soil?


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