Sow what you reap
Collect seeds and you’ll fill your garden with colour ...all for free
COLLECTING garden seed is a great way to fill gaps in your borders and increase plant density for free. And although plants go to seed at different times of the year there is always a rich harvest in autumn...if you know what you’re doing.
You can collect seeds from trees, shrubs, annuals, perennials, biennials, herbs and ornamental grasses.
Your first obvious step should be to harvest seeds from your own garden.
But there’s no reason you shouldn’t increase your range of plants by branching out to local woodland or meadows.
And why not ask friends and neighbours if you can harvest some seeds from their plants?
Different plants have different ways of storing their seeds. They can come in pods, berries and capsules. Many trees produce winged seeds.
If you want to collect seeds from a
plant, remember not to deadhead it after flowering – or at least leave some of the flower heads to mature before removing.
And always harvest seeds from your best-performing plants – why re-grow the runts of the pack?
The most important thing is to collect seeds when they are ripe.
There is no set time – the plant will give them up when it’s ready.
Seedheads often change colour
when ripe, from green to brown, red or black. It’s important to get them when they’re just right.
As a rule, seed harvested when immature will not germinate.
Helpfully, the seeds themselves may also change colour. They will go from green or white to a brown or black colour – a sign they are ready to be collected. They should split easily too.
Flower heads will start to fall apart when the seeds are ripe.
You need to catch them after they have ripened but before they disperse their seeds so check them daily.
As a rough guide, seed is often set about two months after flowering.
But there are some plants whose seed is best harvested when still green and immature, so make sure you research your plants in advance. Here’s my failsafe way to collect seeds:
Paper bags and envelopes work better than plastic for collecting and storing seeds. Choose a dry, relatively sunny day. Place the bag over the pod or flower head so you don’t lose seeds all over the ground, and cut it into the bag. Collect as many as possible.
Take the bags indoors and gently tip them out over some spread out newspaper.
Leave the seedheads for a few days in an airing cupboard or warm, dry room.
The plants should release the seeds, but if not you can gently break open seedheads or shake the seeds out.
Put berries in a fine sieve and mash them. Wash away the pulp with cold water and then leave the seeds to dry out for several days.
For exploding seedheads, you need to check very regularly. Place a bag over them and shake – if they are ripe they should explode into the bag.
If there is surrounding material – chaff – on any of your seeds, clean it off. Chaff can harbour diseases and make seeds unviable.
Research the plants you work with in advance as some seeds, like hellebore, should be sown immediately after collection, because their viability decreases over time Most, however, can be stored until spring – or beyond that – and should be absolutely fine.
Store your seeds in a sealed, airtight container. Placing seeds in paper bags or envelopes inside the container is a good option. I use old Tic Tac boxes – they are small, handy and sealable.
Label all your containers – with indelible ink – so that you know what’s in them! I like to put the name, date, and place where I gathered the seed. I even put a little picture of the plant in there too if I have time.
Dryness is crucial so add something to absorb any stray moisture to stop seeds deteriorating. Silica gel – packs of which come in ordinary household products – works brilliantly.
Finally, store in a cool place. A fridge is ideal. Kept dry at around 5C many seeds last years in this environment.
When spring comes around you will be prepared with a whole haul of your favourite plants. And all without spending a penny.
The most important rule is collect them when they are ripe