WELCOME to a new gardening year! Actually, I was quite busy over Christmas sowing my exhibition onion and leek seeds – I know this sounds early but it is the traditional time of the year.

The main reason is that they have a longer growing season so they will produce large onions and leeks, although their size is down to the breeding and selection. For my large show onions, I’m sowing Robinsons Mammoth White Onion Improved and Robinsons Mammoth Red Onion Improved strains. Although the red makes quite a large onion, it is generally smaller than the white.

I’ve also sown Alisa Craig which from early sowings can make a very large onion, though not quite as large as the Mammoth. It does however have a much better storage life and is a good garden onion.

Another very large strain is the Kelsae – it can be challenging to grow these to the maximum size for shows, but with a little care they can still make quite large onions. They are quite mild in taste but generally have a short storage life, so these types need to be eaten first.

I’m also growing a few onions for kitchen use and for longer storage – these I will sow in early March.

I have also been sowing leeks – no surprise to learn that its Robinsons mammoth Pot Leek strain!

As for all seed sowing in containers, make sure everything is clean and sterile. I cleaned my electric propagators with mild detergent, and washed all my seed containers in a Jeyes Fluid bath and let them air-dry.

When sowing seeds, use a seed compost which has been finer screened (which means it has smaller particles) so that when seed roots do form they do not become clumped in the compost. This can be annoying when you come to pot the seedlings on as this can result in root damage as you tease them apart. Seed compost also has a much lower level of fertiliser so once the seedlings have germinated, you cannot leave them in the container for too long – basically pot them on when you feel they are large enough to handle.

Many gardeners now sow seeds directly into individual cell trays, which is great if you have the space as this avoids the need for lifting and splitting the seedlings and minimises root disturbance.

When it comes to sowing, do read the information on the seed packet – firstly how many plants do you require. The packet will tell you how many seeds it contains, and I always add around 10% extra to my number to allow for potential losses when transplanting or failed germination.

Check if the seed needs light to assist in its germination, which means the seeds are left uncovered – quite a lot do. If they need covering, rather than using seed compost use ‘Vermiculite’ – you will get better results. You will need the finer grade – it’s not too expensive and is widely available. It’s like giving the seed a coat of insulation.

Sowing seeds at this time of year means providing a temperature that they need to germinate – I have used electric propagators on my windowsills (make sure the window is as light as possible, but be careful of any bright sunny days which could scorch the germinating seedlings). Also, if some seeds prefer the dark then these containers can be covered with card to block out the light. Just remove once germination is seeing to be taking place.

Most seeds being sown at this time of the year will require a high temperature to kick-start the seed into germination – an electric propagator is a good tool to help in this.