Time to Sow — Katy in the garden

It’s finally time to start sowing seeds and, over the coming two months, the vast majority of garden seeds will be ready to sow. There’s a lot to think about when planning how, when and what to sow. In past years I’ve set off full of enthusiasm in early March, only to find myself hitting a dramatic real estate crisis come mid-April with seedlings perched precariously around the kitchen wondering when their turn by the windows will come. Several years on I think I’ve finally managed to get organised and to curb my enthusiasm enough to keep things manageable!

1. Setting up

We have very little windowsill space in our house. Last year I (by which I mean Toby) assembled a set of shelves to put next to our south-facing, sliding kitchen door. This was a complete game-changer although if we ever had people for dinner they would be wrestling with trays of plants for seating space. This hasnt yet been an issue due to the pandemic but I’m sure come May our guests wont mind…. This year I upgraded further and treated myself to a cheap grow light (£30) off Amazon and, I have to say, so far the results have been really good. I would never raise seedlings with grow lights alone – it just seems all wrong and sunlight is undoubtedly the best light source for plants – but grow lights are doing a great job at boosting light levels on lower shelves and preventing seedlings from leaning jauntily towards the window.

You don’t need a set of shelves, or grow lights, but it is a good idea to make sure ahead of time that you have a clear idea of your growing space and how to make the most of it.

2. Make a plan

As well as sowing plants for my own garden, this year I’m also growing plants for my parents’ garden where my sister will get married in the summer. This makes finding space for everything and timing it all quite complicated and I’ve ended up making a detailed plan of sowing times.

It’s a good idea to plan out what you’re going to sow and when, and whether you’re sowing direct into modules or into trays/ pots before pricking out and potting on. I find it saves space to germinate seeds that don’t mind root disturbance in small pots. I do this for lettuce and for small seeds like nicotiana, as well as foxgloves later in the summer. The benefit of doing this is that you can have lots of small pots on the go, each with 30 tiny plants germinating and unfurling, taking up almost no space.

When planning your sowing times there are 2 questions you need to ask yourself

- How fast does it grow?

- Is it tender (ie how soon can I bung it outside)?

In the end, when you sow plants will be decided by a subtle balancing act between these two questions. For example, fast growing tender veg like courgettes are best left until May because they need frost protection and they grow incredibly quickly. You can start them in small pots on a windowsill but within a few weeks they will be growing away and before you know it, each of them will be in a 1L pot.

Cosmos and tomatoes are in a similar category, growing so quickly that you’re best starting them off about a month before they could go outside (I’ll start mine in mid-April). Meanwhile the gorgeous tender climber Cobaea scandens needs a long growing season to flower, so they were started in February and are on our windowsill for the long haul!

On the other hand, radish, beetroot, peas and green, leafy veg (rocket, oriental greens, spinach) are hardy as anything. They spend a brief luxurious sojourn in the kitchen where the warmth helps them germinate, but they are soon booted out onto the patio or into my tiny flimsy greenhouse.

Maintaining this balancing act between what needs care indoors and what can go out is the main tightrope walk of April and May.

3. Go steady

A manageable number of lettuce seeds in a tiny pot, taking up very little space

Packets always contain far more seed than you need for a season, which can trick us into thinking we need to sow them all. In fact, it’s much better to sow in small batches for several reasons. First, seeds sown thinly will grow strongly and (crucially) can be pricked out and potted on a little later. If you sow seeds incredibly thickly, you will have to winkle them all out while they’re still quite small. Sown thinly, those seeds can stay in their small pot with room to grow for that extra week that gives you time to make room on the shelf for them.

Secondly, it’s much better to look after a few plants well than neglect hundreds of them. It’s really easy to sit down one evening and fill 6 little 9cm pots with tender annuals, about 20 seeds per pot. These look innocuous now, but in 2 or 3 weeks time you will have 120 plants to find homes for and all hell breaks loose. Sowing one or two things at a time and leaving fast growing, tender seeds a little later will help prevent this crisis so you can give each plant the care it deserves.

4. Ditch old seed

There’s a bit of wriggle room with some seed packet dates, and some seeds store for much longer than others (larger seeds do best), but in general seed is quite cheap and you’re better off ditching old seed packets that are out of date. This year I sowed two packets of lettuce seeds, one in date and one 2 years passed, and the difference was enormous – the old seeds didn’t show at all. Even if old seeds do germinate, if they get off to a poor start the future plant may not perform so well. If you’re stuck for seeds then using old seed is fine, but if you can, buy fresh and save yourself wasted time and effort.

5. Read the packet!

Arty checking planting depth before sowing Cobaea!

This might seem a silly point, but it really helps to read the packet. In general, seeds need to be buried roughly their own depth beneath the surface of compost, but in reality, every seed has its own requirements (surface sowing, light covering, stratification (time in the fridge)). The one exception to this rule is on sowing times. Seed packets often give you the widest possible period for sowing something (to encourage you to buy the seeds and have a go) but it pays to do some research online to find the ideal window. For example they will suggest sowing tomatoes from February, but if you don’t own a greenhouse, February is really way too early. There are some good resources online to guide you, the best of which is the brilliant Charles Dowding who has great advice on specific sowing times.