Lettuces are ideal plants to save seeds from as they do not cross pollinate, which means the seeds will produce identical plants to the parent plant. Below is a step by step guide on how to collect and save lettuce seeds.
- SELECT ONE OR TWO OF THE BEST LETTUCES OF THE LETTUCE VARIETY THAT YOU WANT TO SAVE SEEDS FROM
Choose from lettuces planted in early spring so that they will go to seed when the weather is still warm.
- PLACE A STAKE NEXT TO THE LETTUCE IN READINESS FOR WHEN THE LETTUCE GOES TO SEED
This is to both clearly mark the plant as one that is being saved for seeds and in preparation for securing the plant in an upright position as it grows taller.
- ATTACH A LABEL TO THE STAKE IDENTIFY THE VARIETY OF LETTUCE
This is because, while various varieties of lettuce look distinctly different when ready to harvest, some varieties begin to look more like each other as they go to seed, so much so that it can be difficult to tell them apart. As lettuce seeds stay true to type and a single lettuce plant produces far more seeds than one gardener can
possibly use I generally only harvest seeds from one plant of each lettuce variety. And as lettuce seeds keep for five years, I do not collect seeds from every type of lettuce that I grow every year.
LEFT: Staked and labelled lettuce plant just prior to full flowering. RIGHT: lettuce seed heads ready to be harvested. The heads are ready to harvest when 50% of them are showing the feather like pappi.
As the lettuce plant begins to go to seed it will grow much taller and heavier at the top as the seed heads fill out, which increase the risk of it toppling over. To prevent this tie the plant to the stake.
At this stage, the plant appears to be drying out, but what it is in fact doing is transferring all its energy to the seed heads. So keep the watering as you would normally do for lettuces.
As lettuce seed heads get close to shedding their seeds they first flower, then as the flowers wilt they give way to pappi, the white feather-like parachutes each seed has to propel it further from the parent plant when the seed heads burst open.
The heads are ready to harvest when around 50% seed heads have formed their pappi.
The best way to harvest the heads is to cut the branching stems off where they are attached to the main stem. Each branch usually has about twenty to forty seed heads on it.
It is a bit if a dance as to when to harvest. If you cut the heads too early the seeds will not have matured enough. Immature seeds are usually a greenish colour and flatter than fully mature ones. But if you leave the seed heads too long they will start shedding their seeds. If a strong wind blows up you can lose almost all the seeds in a single day.
- GET A LARGE SHALLOW BOWL AND STRIP THE SEED HEADS FROM THE BRANCH STEMS INTO THE BOWL BY RUNNING YOUR HANDS ALONG THE STEMS TOWARDS AND OVER THE SEED HEADS.
- CRUSH THE SEED HEADS WITH THE PALM OF YOUR HAND UNTIL ALL THE HEADS HAVE BROKEN APART
- PICK OUT THE HEAD FRAGMENTS AND ANY PIECES OF STEM
- SWIRL THE BOWL IN A CIRCULAR FASHION
This will concentrate the seed and remaining small fragments in the centre of the bowl with the heavier seeds on the bottom and the lighter fragments on top.
- BRING THE BOWL CLOSE TO YOUR FACE AND GENTLY BLOW AIR INTO IT TO DISLODGE THE LIGHTER FRAGMENTS FROM THE BOWL
But close your eyes when blowing to prevent any fragments getting in. Don’t blow too hard as you will blow some of the seeds out as well.
- REPEAT THE PROCESS UNTIL YOU ARE LEFT WITH ONLY SEEDS
- PACK AND LABEL THE SEEDS THEN STORE THEM IN A COOL DRY PLACE.
When labelling the seed packet it is also a good idea to put the use by date on it. In the case of lettuce seeds it is five years after the seeds were harvested.
Stripping the heads from the stalks.
Blowing the lighter fragments off the top of the seeds.
Lettuce seeds after the winnowing process has been completed.