mini-series episode 2 | beginner's guide to sowing techniques
This first episode covers garden terminology which can feel a little intimidating if you are a beginner. Sarah and Arthur explain useful gardening terms and plant types and why it is good to understand Latin plant names. They also give a brief overview of their gardening year – describing a few simple jobs they do each month.
in this episode, discover...
- How to grow a cutting patch or veg garden from a windowsill or cold frame
- Sarah and Arthur describe how they grow from seed and the different methods they use
- Why you should treat seed like gold dust
- Tips for getting children sowing and growing
- Sarah’s easy to remember 5 Ts for direct sowing success.
Arthur's top tips for windowsill propagating
Consider light levels
If sowing from window boxes don’t sow too early as you will end up with leggy plants. Seedlings need lots of light which is why cold frames are ideal. Indoors, often rooms are too dark and warm so start sowing towards the end of March, rather than at the start of the month.
Rule of a baker’s dozen
Arthur’s advice is don’t try to grow 100s of seeds. Sow less, make it fun and really nurture the ones you sow. He follows the rule of sowing no more than a baker’s dozen, 13, seeds.
Fill seed trays or modules
Pack seed trays or modules properly with moist compost to give your seeds the best head start.
Use square pots
When potting on, use 9cm square pots to maximise your windowsill space.
Sarah’s top tip
Treat seeds like they're gold dust
Sarah advises thinking of seeds like gold dust. Most beginners think, the more I sow, the better results I’ll have. The reverse is true. Instead pour seeds out onto a white surface, like a saucer, and place individually into the tray so you can see them, then gently push them in or lightly cover according to the packet instructions.
Keeping seeds fresh
Keeping seeds cold and dry helps them last. Silica sachets help keep air dry in a seed tin or tupperware, ideally stored in the fridge or somewhere cold.
Sow straight into the ground. This works best on freely drained soil and suits plants that don’t like root disturbance and germinate quickly and easily once the soil is warm. This includes vegetables like radishes and lettuce, and ornamentals like poppies, grasses and dill. Meadow seeds are also sown direct. For it to work well, you want the soil to be warm and moist, as it is in April and September, and have a fine tilth. Sow as thinly as you can and then thin the seedlings to the spacing recommended on the back of the packet. Don’t thin meadows, just leave the seedlings to get on with it cheek by jowl.
Sarah’s easy to remember 5 Ts for direct sowing
Although Sarah does little direct sowing at Perch Hill due to the heavy clay soil, if you have cracking soil here are her top tips.
1) Timing – don’t sow too early, wait until the soil is warm. If weeds are popping up, it’s a sign nature’s doing her thing and a good time to direct sow.
2) Tilth – aim for a nice crumbly apple crumble topping.
3) Thinning – once seeds have germinated and seedlings are 2-3cm high, go in and thin out – go by seed packet instructions but roughly one seedling every two inches.
4) Transplanting – trowel everything between the final distance, and with all the little seedlings in between, make another row from that.
5) Tie in – with almost all productive plants 45cm up, you will need to stake and tie them in – Sarah does this at the seedling stage. For more information read Sarah’s article on staking plants.
Sowing under cover
Sarah sow lots of things under cover, particularly if planting in beds on heavy soil. Germination is quicker and more reliable in a protected environment. You can plant out at the correct distance, wasting almost no seed or time with thinning, and you can carry on sowing all year, whatever the weather. It’s also better than bending over or scrabbling along on your knees.
To germinate most seeds, you want a warm, moist, dark environment. Sarah usually covers her seed trays or modules with empty compost bags to enclose moisture and warmth and keep out the light. She then checks morning and evening for any signs of germination. Trays must then be uncovered and put in a place of maximum light. Sarah uses a homemade propagator bench set at 20ºC to assist germination - see below.
They do very little traditional sowing into small rectangular seed trays at Perch Hill, only using this method for tiny seed that is difficult to sow individually, like antirrhinums. Pricking out and potting on is too much of a palaver. If you prefer this method, sow seeds thinly into moist seed compost, following the spacing on the packet or, if the seeds are like dust, in tiny pinches. Gently push seeds into soil or cover lightly, again according to the packet instructions. Arthur recommends half seed trays made with heavy duty plastic. Capillary matting under trays helps to retain moisture and minimise watering.
This is when you move baby seedlings from a tray with all their siblings into a pot on its own. When seedlings have two ‘true’ leaves, use a teaspoon or dibber to gently tease the seedling out, don’t touch the stem, that can kill the little seedling.
Some plants like cosmos will thrive having roots disturbed by pricking out and potting on. Others, like zinnias, will sulk. Plants known for not liking root disturbance are sweet peas, nigella, poppies and basil.
For these seeds, try growing them in Jiffy Pellets, which are made of peat-free coir. Sarah and Arthur use peat-free Jiffy trays for lots of vegetables and flowers. These are ideally suited to tomatoes, aubergines, chillies, Florence fennel, lettuce, sweetcorn and celeriac – plants that hate having their roots disturbed, as well as any of the larger seeded flowers like nigella, foxgloves, cosmos and zinnias. Sow 2 seeds to each cell. If both germinate, remove one and avoid the task of pricking out. The large (45mm size) coir Jiffy pellets are the ones to use. With this large size you don’t need to pot the seedlings on before putting them out in the garden, remembering to remove the net before planting out. The plants are big enough to survive as they are.
For this reason, Sarah also uses Jiffy trays for pricking out the few seeds we do sow into conventional seed trays. These take up a fraction of the space of tons of mini pots. Once the roots have filled the net, which usually takes 2-4 weeks, remove it to allow the roots to run free. This is important, as leaving the net on really holds them back. Then plant them out. Children especially enjoy this easy sowing method. Read Sarah’s articles on how to get children sowing and growing for more information.
Sarah uses rootrainers (long, thin pots, available from our website), or cardboard loo rolls, for shrubby herb cuttings like rosemary, thyme and sage. They are also brilliant for sweet peas and beans (broad, French, borlotti and runner). All legumes, these included, will thrive with a long root run. When the seed first germinates, it puts down one long root. This breaks off when it emerges into the air at the bottom of the pot and, as with pinching out the tip, the root then throws out lots of side shoots. When these reach the edge of the root trainer, they slot into a channel in the side of each cell and are directed straight to the bottom. They then break off and you get a circle of root development, so the new root system forms very quickly. If you sow into a short, stumpy pot, there is less initial root to branch. Longer root - more branches; quicker, bigger plant
Sarah and Arthur do some sowing into small, individual pots for the plants with larger seeds. Amongst the veg: courgettes, squash, pumpkin, gourds and cucumbers, and amongst the flowers: cobaea and sunflowers, are all difficult to get into a Jiffy and their large seeds with a big surface area, rot easily in the compact pellet. Fill the pots with peat-free potting compost and water and push the seed in to the depth of your knuckle, vertically rather than flat. Biodegradable pots are ideal for this. When the seedling is at the right stage to be planted out, just pop the whole thing into the ground. These are also ideal for plants that don’t like root disturbance.
Sarah sows loads of things, particularly herbs and salads, into lengths of guttering. They germinate quickly and consistently, all cosy somewhere light and warm, and the whole lot can be transplanted outside in one go with ease. She sows most of her salad, peas and cut-and-come-again herbs (like chervil, coriander, parsley and basil) and edible flowers (like nasturtiums, cornflowers and calendula) into the gutters. Most of these herbs and many of the salads crop well for 2-3 months, but they need replacing as soon as they start getting tired. Serial sowing every 8 weeks, with a new generation coming along somewhere else in the garden, is the ideal, but Sarah often has a chock-a-block vegetable plot without a chink of room. Sowing salads and herbs into pipes in the wings is an efficient way of growing salad to pick all year. The plants from these can be slotted in, ready to pick as the garden lot come to an end. You can buy guttering from larger hardware stores. Arthur doesn’t use gutters but does sow successionally and will pot on into 9cm square pots.
Wooden or polystyrene crates
In the winter, Sarah grows dill, coriander, parsley, chervil and basil in empty wooden wine cases, or in polystyrene fish boxes with holes in the bottom. Fill the crate with compost and, once a fortnight through the winter, sow a whole packet of seed. Cover them with cling film to enclose the moisture and put the boxes in the greenhouse or cold frame on a heated base. Your airing cupboard is fine but, grown in the dark, you’ll need to check every 24 hours for signs of germination. Move the seedlings into the light as soon as there are any signs of green and remove the cling film. Allow the plants to reach about 3 inches and then start cutting. You should get two or three cuts from the same root stock.
A home-made Propagator bench
Black plastic or empty, split open compost bags
Horticultural electric blanket attached to a thermostat on the side of the table.
Polystyrene insulating sheeting
Top easy seeds to grow
Hollyhocks - sow in April-June in a sunny spot to flower the following year and should self sow.
Sunflowers - for a lovely annual display Arthur recommends sowing sunflowers - so many wonderful varieties and great to grow with kids.
Calendula ‘Indian Prince’ – easy to grow for beautiful orange flowers with a crimson reverse.
Potatoes – fun to grow as a beginner for the tombola thing of picking out potatoes one after another – you can’t believe one tuber has turned into 20 potatoes.
Dahlias - you have to plant a dahlia tuber (which look like salamis). Pop in a decent sized pot 6 weeks before your last expected frost, often the last week in March and plant out after the frosts have passed.
Linaria marocana ‘Sweeties’ mix – a jumble of brilliant, pretty colours, with mini snapdragon flowers and scent. These are super quick from seed to flower.
Poppies love to be scattered and are easy to direct sow.
Sweet peas – beautiful, scented, cut-and-come-again, easy to grow and a nice big seed to handle too.
· Seed trays – for tiny seeds where you cannot separate them out e.g., tomatoes and antirrhinums
· Rootrainers – for legumes or sweet peas - long thin root run and channels down the side help with rapid root formation
· Square individual pots – for big seeds such as Cobaea scandens, courgettes and cucumbers
· Guttering – for salads, herbs, kale and nasturtiums and calendulas that grow in large numbers
Find out more
Sign up to Sarah’s weekly gardening tips email (navigate to the bottom of the page and submit your email)
For Sarah’s simple guide of monthly gardening jobs see this month in your garden on our website.
Detailed growing instructions are sent out with every sarahraven.com order and you can find our instruction booklets on our website too.
In our growing guides you can find everything you need to know about growing and caring for specific plant varieties.
A Year Full of Flowers, Gardening for all Seasons by Sarah Raven
Tracing the year from January to December, Sarah's latest book provides inspiration, planting ideas and expert advice for a beautiful garden all-year round.
The Flower Yard by Arthur Parkinson
The Flower Yard follows Arthur as he gardens through the seasons in pots. It is a beautifully visual yet personal and highly informative read on his love for bold colours, cut flowers and bees. Especially helpful for those with small gardens, patios and balconies seeking floral exuberance and escape.
Sarah and Arthur run gardening courses at Perch Hill and around the country, including The Cutting Garden, A Year Full of Flowers and Magnificent Pots.