The days are short, damp and dark, but Jo Arnell doesn’t care – she’s got her head deep in the seed catalogues.

As soon as the last Christmas card is in the recycling, or even before, I am flicking through the seed catalogues. Every year I promise myself that I won’t buy so many, sow too many, won’t go too mad. After all, I have a good stash of home-collected seeds already – and not much time or space even for these. But I’m going to have to admit to you, right here on the page (imagine I’m standing at the back of a room somewhere) that I am totally addicted to seeds.

I just love the magically simple act of sowing a few tiny grains and watching a plant (an actual plant!) burst from something minuscule and inert looking. It is so exciting. It isn’t always as easy as this though, and things can go wrong.

If you have ever tried to grow something from seed and failed, take heart, because it probably wasn’t your fault. Seeds need to be triggered into germination. Most of the time annual seeds just need a bit of warmth and moisture (and sometimes light) to get going. Annual plants have but a short time to do their stuff, so are in a bit of a hurry. Perennials may take longer and some need to go through a period of winter before they will even think about germinating.

What a seed needs

Warmth  Plants have evolved over millennia to recognise when spring has arrived. Seeds are primed to germinate in the warmth, as this means that conditions for growth and the chances that they will make it to maturity, have improved. Some plants need more warmth than others, depending on where they have originated in the wild. Notice how a great rash of weeds pops up as soon as the weather outside starts to improve and take your cue that the conditions for sowing directly outside into the soil are just right.

Moisture Again this is a spring thing and to do with plants being in harmony with the seasons. Whether it’s a thaw in an alpine meadow, a rainy season, some April showers, or a dribble from your watering can, exposure to water will nudge plants into growth.

Light This is not always needed; seeds normally germinate under the ground and until they have grown a leaf containing chlorophyll, they cannot photosynthesise. Instead, they respire and therefore need oxygen more than light at the point of germination. Very quickly after this though, they do need light; bright and indirect, in order that their delicate new leaves don’t scorch. Seedlings quickly become etiolated and leggy when it isn’t bright enough, so if you are growing them inside, a warm and bright north facing windowsill should be perfect.

Soil Because seeds need oxygen for germination, it is important that the compost is free-draining with lots of tiny air pockets. Seeds bring their own food with them (which is why we eat them), so ordinary ‘grown up’ compost may be too rich. Seed compost (available at most garden centres) has been specially formulated to be finer, and grittier and more suited to the needs of seeds and cuttings. As soon as the seedling grows its first pair of true leaves, it needs to be potted into a richer mix.

Vernalisation (winter dormancy) This is plants’ way of making sure that tender seedlings don’t start growing at the wrong time. It normally happens with perennials and woody plants. You may need to sow the seeds in the autumn and leave them outside in a sheltered place to go through winter, or cunningly put them through a fake winter in a bag of damp sand in the fridge for a bit in order to break their dormancy. Seed sowing instructions should be provided by the producer, so do not use this method unless it is indicated – or if all else has failed. Do warn your family too; it’s annoying if they discover and disturb (and possibly tip away) the contents of the mystery package…

Direct sowing versus sowing under cover

It’s easy and very tempting to empty the packets into your hand or pocket and go scattering seed around the place. After all, this is what the plants themselves do and if you like the self-sown, slightly random and natural look, then this could be the method for you.

The problem comes when the seeds start germinating, because they usually do this at the same time as all those other random self-seeders – the weeds. But if you are sowing vegetables it pays to grow them in neat rows, as you can then hoe in between the rows and keep the weeds to a minimum.

There is also a neat trick, which involves preparing the soil, waiting for a couple of weeks until the weeds pop up, then hoeing them off – without disturbing the surface too much. You can then sow your seed into the clean soil. The same method can be used in the borders with annual flower seeds, but here you can vary the shapes; rigid rows of flowers are great for a cutting garden, but less natural looking in a mixed border.

Sowing under cover and then pricking out and potting on seedlings is a time-consuming task, it’s true, but it will give you ultimate control over where exactly your plants are to grow. The other big advantage – and this is the reason I tend to favour it – is that you can protect your tiny plants from the ravages of the unpredictable spring weather and worse: attack from pests.

Tender plants

“To extend the flowering season, I often sow two lots of annual flowers”

If started off early these must be sown indoors and will need bottom heat for good results. You can buy an electric propagator with a clear plastic lid to keep the plants in their own mini greenhouse environment. A warm window sill might just do the job, but watch out that your babies don’t scorch in the early spring sunshine. The advantage of sowing early is that you’ll be able to get a head start on the season and have a display of flowers or a crop of vegetables earlier in the season.

Tomatoes, for instance, need a long growing period in which to grow and ripen their fruit. Our summers aren’t always as long as the one we experienced last year, so the earlier they are sown, the earlier you will be picking ripe tomatoes.

To extend the flowering season, I often sow two lots of annual flowers like Cosmos and Nicotiana; one under cover in late winter and then another, directly into the borders once the soil has warmed up in April. There can still be frosts until May though, so watch the weather forecast before putting tender plants outside.

Hardening off

This is a process that entails gradually accustoming your sensitive seedlings to life outside in the garden. Start by putting them out for a few hours each day, bringing them in as the temperatures drop in the evening. Cold frames and cloches are a useful half-way house, being sheltered, but unheated. After a week or so the plants can be left out and then planted in their permanent positions. If they are shoved outside unceremoniously, they may, like some of us, get a hard shock and then fail to thrive, or worse…


We are not necessarily growing vegetables to save money. As my father-in-law points out, a cabbage at the shops is only 50p (and has less caterpillars in it), but there is immense satisfaction in growing something from scratch, perhaps an otherwise expensive crop that is hard to find in the shops, a weird and wonderful blue potato, or deliciously unusual variety of kale. Who wouldn’t want to grow a tomato called ‘Black Krim’, or a leek named ‘Gladiator’? Last year I grew a fantastic variety of Swiss chard called ‘Pink Flamingo’ which had shocking pink stems. Nobody wanted to eat any, but I was extraordinarily proud of the plants and they looked gorgeous.

One of the other great things about growing vegetables from seed is that most of them are annuals, so are raring to grow and will germinate almost as soon as you open the packet. If you buy F1 hybrids, they have been bred to be reliable and uniform – to do exactly what it says they’ll do on back of the pack.

On the other hand, heritage or heirloom varieties are those that have been bred down through the generations for their unique characteristics. These are more likely to have been cultivated for their flavour and may look less tidy and regular, but will probably taste amazing. You can also collect the seeds of heirloom veg to sow again next year. Do not bother to collect the offspring of F1 types though, because the next generation will revert back to another previous, less desirable strain.

It’s still too early and too cold to start sowing much this month, but we can be making plans (it’s what keeps me going in these cold, dark days). Let’s stay in the warm, peruse the sumptuous seed catalogues and dream of the spring. It will be here before we know it.

Pick of the catalogues:

Chiltern Seeds great for both flowers and vegetables.

Sarah Raven wonderful, inspirational pictures and colour schemes.

Special Plants some unusual varieties and lots of good information from an expert.

Kings Seeds  a good selection of vegetable seeds and great value.

Seeds of Italy very generous quantities and some lovely varieties.

Contact Jo for details of her courses and workshops: 
01233 861149


Seedpod of Nigella ‘African Bride’

Seedpod of Nigella ‘African Bride’

Self-seeding annual opium poppy ‘Lauren’s Grape’

Self-seeding annual opium poppy ‘Lauren’s Grape’

Cosmos ‘Double Click Rose Bonbon’

Cosmos ‘Double Click Rose Bonbon’

Centaurea cyanus annual cornflower

Centaurea cyanus annual cornflower

A ‘meadow’ in my garden, all annuals from spring-sown seed

A ‘meadow’ in my garden, all annuals from spring-sown seed

Home-collected seed

Home-collected seed

(Instant) Climbers

Sue Whigham explores a need for speed...

A Courting Couple

The courtyard gardens at the Chelsea Flower Show this year were, as usual, incredibly popular with the public. Once the Show was in full swing it was hard to get near them to admire the sheer ingenuity, imagination and love...

A Garden for all Seasons

Follow Jo Arnell’s spring tips for a gorgeous garden all year round