Sowing Seeds Indoors – The Do’s and Donts

Sowing Seeds Indoors.

sowing seeds indoors

The first of our Seed Sowing guides will focus mainly on sowing seeds indoors. Whether it be on a sunny windowsill, heated propagator or in a seed sowing greenhouse, the principals are basically the same.

Why do we sow seeds indoors?

There are many advantages to sowing seeds indoors/ under glass. The added protection they gain from the cold and windy weather at this time of year allows for some of the more tender seedlings to establish themselves. When the outside temperatures rise enough to start planting seeds outdoors (normally around May-June), the seedlings started indoors, will be sturdy enough to plant out. Meaning the seedlings will ultimately spend less time reaching maturity when they are eventually planted out, allowing you to maximize yields and save on space.

sowing seeds indoors
Mini Propagators, Seed Sowing tray, and Compost

When can I sow seeds indoors/ under glass?

If your lucky enough to have a large warm windowsill, heated greenhouse/ propagator, then it is possible to start some seeds as early as January. When sowing seeds indoors it’s important to make sure the temperature is consistently around the 13° – 22° mark. When planting any seeds, it is important to pay close attention at the information/ growing guides printed on the packaging. These guides normally provide you with an Indoor sowing date, an outdoor sowing date, and a planting out date. While the temperatures in parts of the UK and Ireland can vary greatly, these are often just a rough guide, and you will soon learn how to work with the weather in your local climate.

What seeds can I sow indoors?

You can technically grow any seeds indoors, but some will appreciate the extra heat and warmth more than others.

  • Tomatoes
  • Peppers
  • Okra
  • Aubergine
  • Chillies
  • Lettuce
  • Kale
  • Swiss Chard
  • Khorabi
  • Herbs

All of these seedlings are susceptible to a cold frost and are often much better starting indoors at least until the last frosts have cleared.

It is also possible to start garlic and onions bulbs in sets indoors.

sowing seeds indoors
Garlic Bulbs

What can I sow my seeds in?

There are any number of different sized plug trays, pots, and containers designed for sowing seeds. Basically, if you can put soil in it, and it is not too small then you can sow seeds in it. A garden shop bought seed tray will work just as well as an empty yogurt pot. Seed trays are  inexpensive and we tend to get ours from discount/pound shops. They are also reusable, noting it is important to clean them thoroughly after each growing season, to avoid cross contamination and spreading any diseases. Using designated seed trays and plug trays are handy, as it’s possible to purchase existing plastic or glass covers to the correct size, and are often designed to fit the shape of a standard windowsill.

The size of the seeds often determine the size of the container that you sow your seeds in.

Small Seeds e.g. herbs, cauliflower, broccoli. I often sow these randomly over a seed tray, and once the seedlings have started to develop a true leaf, are often pricked out into larger containers.

Medium-sized seeds e.g. Peppers, Chillies, Lettuce. I often sow one or two at a time into an individual plug. The reason why I sow two at a time instead of one is in case one of the seeds doesn’t germinate. If both seeds germinate then one is removed. I often use these individual plugs to keep trays of lettuce and salad crops ready to fill up any gaps or empty spaces I might have within the plot.

Large Seeds e.g. Courgettes, Pumpkins, and Sweetcorn. I often sow these into small individual pots ( 3” – 5”) as they require more growing space for their root systems to get well established.

sowing seeds indoors
Sowing seeds

What is the best type of soil to sow seeds in?

Seeds can be sown in any soil, buy you are much better off starting your seedlings in a seed sowing & cutting compost. These composts are sieved well and contain fewer larger pieces of bark and stones, anything that may restrict a seedlings growth. They often contain large quantities of loam, allowing the compost to retain moisture while repelling nutrients which can be harmful to seedlings.

sowing seeds indoors
Heated Propagator

There are no right or wrong ways when it comes to sowing seeds. And you will soon realize that some just work better than others. The winter can be a very long period for keep vegetable growers. Starting some seeds indoors and caring for them, helps take the edge off until Spring time comes. Over time you will find your own preferred methods, containers and sowing compost that works best for you.

Sowing Seeds – Our guide to Growing Seeds

Sowing Seeds

sowing seeds

Here is how us fellas here at growblogs go about sowing seeds. We’re not ones for spending frivolously on the allotment and with the average price of an onion costing us well in the £1’s last year, it was an expensive year, but many of those costs incurred in the first year were one offs or will not need replaced for many years to come. Our free from the internet shed has cost well over £200 in repairs and fixes. The raised base alone, which we hadn’t budgeted for was nearly half the total amount above.

sowing seeds


In 2016 it’s our aim to be as economical as possible with our purchases. we’ll be attending seed swaps if we can find them and if not creating our own one on the allotment. We’ll be growing from seed wherever possible and really taking our costs down to a minimum across all areas. Any ideas you want us to go into great detail on, please let us know and we’ll put our heads together for you.

Today we’re talking about Growing from Seed or otherwise put “What is the correct method for sowing seeds”. Growing from seed is extremely cost effective especially if you are in an allotment or gardening club. Sutton seeds ( offer huge savings on seeds and other discounts across their product range for those in gardening clubs. This means with some careful planning you can have many years growing for very little cost.


Sowing seeds indoors allows for an early start to the season and ensures you can get a head start, especially if the weather is horrible. If you have window space, this is an easy way to get your plants started. Here’s how we sow seeds inside.

  1. Fill seed trays 1/2 full with seed compost. Seed compost is vital here as this has a nutrient content perfect for early seed growth and development. Don’t be tempted to use normal compost as your results may not be the best. Moisten the compost, don’t soak!
  2. Take a pinch of seeds and sprinkle them over the compost. Leave an inch or so between each seed and then add another 1/4 layer of compost on top.
  3. If you buy a small plastic cover “propagator” to cover the seed trays, this is an inexpensive way to ensure the seeds don’t dry out. We have also had great success using sandwich bags tied with an elastic. Both should post less than a fiver.
  4. As soon as you see seedlings emerging from the compost it’s time to remove the cover. Usually it’s best to wait until the second set of leaves grows before transplanting, fertilising or thinning.
  5. When the plants are ready to be moved, it’s now time to consider the end goal. Plant the seeds in a pot big enough to cope with their growth until they are ready to be transplanted into the soil. We have built our own cold frame, which will be used to harden off the seedling and help them sustain their growth right up until planting. Using pallets, a free from the internet glass door and Chris’s won screws, the cold frame cost us nothing, but will help us ensure the best success for our plants.

sowing seeds

N.B Remember all seeds are different and have different growing requirements. We always stress the importance of reading the packets for the correct growing instructions. We also take no responsibility for the growth of your seeds, no matter how awesome the results may be…

Let us know your plans for sowing seeds successfully and if you have any of your own tips to add.


Over Wintering Broad Beans – Getting Ahead


Over Wintering Broad Beans
Broad Bean Seeds

Here is our guide to over wintering broad beans, check back later in the year for the results.

Back In September I read an article on the Express website titled “Coldest Winter for 50 YEARS set to bring MONTHS of heavy snow to the UK”. They warned us “Sub-zero temperatures and violent snow storms could hit as soon as late October as a freak ocean cooling in the Atlantic threatens to trigger a historic, nationwide whiteout.”

Now im no meteorologist but I do own an allotment, that means im an expert on the weather and here where I sit now in Belfast, I still haven’t seen one snowflake this side of Autumn. In fact almost daily im seeing pictures on my followers twitter feeds of veg still growing well outdoors. Brussels Sprouts are reported to have generally increased in size by a third from last year due to the unusually mild Autumn. As of Sunday the 10 Dec we still has a small pot producing delicious mixed lettuce leaves, and my friend was asking if id came across any unusual ketchup recipes because he was struggling to preserve all of his late crop of greenhouse tomatoes..

Rather stupidly I believed what I read and decided that I must get the plot ready for winter, and on a Saturday middle October I prematurely dropped my bean and pea supports, stored the bamboo canes and composted the plants which could possibly still be fruiting today.

Over Wintering Broad Beans


Isint hindsight a wonderful thing. We know now that, to sow our broadbeans early November would have been the perfect time. Once again we were put off by scaremongering tales of a Winter scene C.S Lewis himself would have been proud to have described. So we held off and held off, until I decided enough was enough and I purchased some seeds and a new thermometer for the shed. I bought the seeds from Premier Seeds Direct and they arrived very quickly and look to be of great quality.

So to Over Wintering Broad Beans

Overwintering Vegetables means growing vegetables over the winter period which will often result in restricted water supply to the plant, frost and reduced sunlight. One of the main benefits of sowing before winter is that you can often expect to start harvesting the plants up to a month before those grown in the Spring. Over Over Wintering Broad Beans are also much more resistant to blackfly. Aquadulce Claudia is widely regarded to be the premier choice when it comes to Over Wintering Broad Beans , it is long podded, high yeilding, matures early and is most importantly very tasty.



The beans will be planted 3 Inches deep, 8 Inches apart in rows 18 Inches apart. I plan to plant one row half with overwintered Beans so that I can compare it with beans that I will sow in Spring.

As I had already prepared and covered my peas and beans bed for next year, the only thing I am going to lose by planting them now is the seeds themselves, and you can assure yourself that as soon as seed hits soil this Friday Jack Frost is going return with a vengeance.

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Coldframe Construction – Building One Yourself, DIY

coldframe construction
Finished Product

Coldframe Construction

This weekend in the midst of hurricane Desmond battering Belfast, I took to the blogs and to twitter to connect with some other allotment folk and to introduce our blog to them. Chris on the other hand got stuck in and built our very first Coldframe construction.

The wood primarily came from pallets and floorboards which had been salvaged. We are very keen to recycle as much materials as possible. The door with the glass was pulled of a skip (with the owners permission) last summer with the intention of constructing a coldframe. The only part of the structure that we had to pay for were the hinges, even the screws were free as Chris won them on a scratch card after making a purchase at Tradepoint at B & Q.

Last year Chris’s kitchen and living room windows were covered from top to bottom in sprouting seeds he had begun to grow indoors. However when it came time to plant them out, we got hit with a cold snap and months of work had been ruined overnight. it was then we agreed that making a Coldframe construction to keep our seedlings safe in the process of hardening them off for outdoor planting, was a good idea.


coldframe construction
Materials Used


coldframe construction
Coldframe Construction

Our process for hardening off seedlings will follow something like this to ensure we gradually introduce them to the elements

  1. Place seedlings into the coldframe construction to protect them from strong sunlight, potential frosty nights and less-frequent watering. This will take approximately 1 week
  2. As the temperatures start to rise, we’ll open the cold frame roof for a small time of approx 2-3 hours of sun. Another 2-3 days.
  3. Increasing the time the seedlings are exposed to the elements but closing the lid as and when more serious weather systems come into play – 1 more week

Transplanting the seedlings into the ground when they have successfully hardened off will give us the best chance of growing from seed, something Chris and I are very happy about as the cost savings will be huge.

coldframe construction

Choosing a Polytunnel – A helpful guide







So the boys here at growblogs are in the market for a polytunnel. This was a decision we made long ago but decided to hold off until the start of the next growing season to save our new purchase a harsh winter. There are many advantages to growing in a polytunnel compared to just growing in the open ground.

Growing Season – One of the main advantages of owning a polytunnel, and one that for us in particular due to our location in Northern Ireland, is the fact that you can greatly increase your growing season. It is possible to start the season from 2 – 6 weeks early, and extend it by roughly the same, dependant on location. We reckon that here in Belfast, that could give us a good 7 – 8 weeks extra growing time which will greatly increase our yield.

Temperature – The temperature inside a functioning polytunnel will be significantly greater than outside, and will vary easily. It is possible to continue growing all through the winter by introducing heat into the tunnel in various ways.

Variety – There are certain types of fruit and vegetables that are only able to be grown in greenhouses or polytunnel. Certain heat and light loving varietys would just not be possibly for me to grow without the finest of summers. Tomatoes, Cucumbers, Chillies and Courgettes all need good conditions to grow well and they just would not be an option for us to grow out doors.

Protection from weather – Polytunnels have their own micro climate and if well sealed and airtight, will keep the contents well protected from the elements.

Protection from pests – The protective film creates a barrier to the insects from your crops. However they will try everything possible to get inside and if they do find a way in, finding their way out will seem fruitless and difficult.

The only real disadvantage they we have discovered so far, is that you cant leave it up to mother nature to water your covered crops. There are ways around this with many automatic watering systems on the market and many more ingenious methods amateur gardeners have been perfecting for years.

Off to the shops.

One of the best friends to modern man is online shopping. The ability to browse countless products and have them delivered to your home all from the comfort of your pyjamas. At first when I googled “Polytunnel UK” I was slightly overwhelmed by the amount of online shops, sell many types and sizes and the greatly varying prices between some of the products. It was then that I reliased that I was gonna have to do some some research to get the most bloom for my buck.
Having spent a few hours going through all the websites and everything I could find on the subject online I came to the conclusiuon that a) there is actually very few differing products, ans b) the difference between quality and price differs greatly.

The cheaper polytunnels come with a green mesh cover as compared the the much dearer clear filmed covers.

The online sites that sell these products explain in detail the science behind the different tunnel coverings and give advice on which would be the best for your own needs.



One of the reasons why I believe there is a lack a of a good mid range polytunnel is the commitment that it takes to make the most of the tunnel. Gardening for many people can be a fly by hobby, falling into the same category as golf, fishing and many other activities of whose accessories litter roofspaces and garages throughout the country. When speaking to our fellow allotmenteers there has been countless stories of people being offered a new plot and they go at it all guns blazing for a few months, then as soon as the weather changes or the novelty has warn off, they are never to be seen again. When you receive a new plot it can very much feel like your playing catch up with your neighbours. It can be disheartening looking at a bare plot when all around you are neatly spaced rows of lettuces and gleaming greenhouses. Often the temptation could be to throw some money at the problem and purchase a cheap polytunnel to cover that bare ground and get the growing process underway. These hobbiests are unlikely to spend upwards of £800 on a polytunnel unless they are determined they are in it for the long haul.

While the smart money says “its an investment, “it will pay for itself” the best part of £1000 is a lot of money. If I knew the polytunnel was going in my garden or field where I lived it would be a lot easier parting with the money. Ive been warned about leaving valuable tools in our shed, due to thefts, that im sure occur on allotment sites all over the country. Also random acts of vandalism, that do happen, it only takes a small knife to do a lot of damage to a polythene structure, and we all know there are lots of people out there they who enjoy nothing more than spoiling other peoples fun.

Mother nature can also be a polytunnels enemy. Wind would be a particular issue. While every attempt will be made to firmly secure the tunnel accidents do happen and a particularly strong gust of wind could literally see your investment take off.

Taking all of this into consideration and at our next monthly Growblogs Directors meeting (down the pub) we will be weighing up the options do we go a) cheap and cheerful, b) costly and concerned or c) do we try and build our own like the shed which turned out, cheap and cheerful at first then turned costly and caused much concern.