My Smart Garden

Why save seed?

There are many great reasons to save seed. It’s much cheaper than buying seed, but the most important reason is that plants adapt plants to local conditions, to the soil, rainfall, and heat – over time. This process is called naturalisation and takes 7 years. This means you have healthier plants that need less watering and fertilising. They are also more resilient to pest and disease. This is particularly important with climate change and uncertain futures.

Selection – choosing plants to save from

It’s very important to collect seed from the best, healthiest plants. Never collect seed from plants that haven’t grown or produced well! The genetics are passed on the to the next generation.

You can only save seed from open pollinated plants. Many plants are hybrids (F1) and the seed of hybrids will usually not produce fruit. It will say on the seed packet if the seed is hybrid, but not usually on a seedling punnet.

Plants put a lot of energy into producing seed and take a lot of nutrients from the soil when producing seed, so choosing the right plants at the right time is important.

For fruiting plants with the seed inside the fruit, like zucchini, tomato, pumpkin, beans, and peas, the plants slow or stop production when producing seed. It’s best to wait till the end of the season to collect seed.

For leafing plants, like silverbeet, broccoli, lettuce, choose best few plants for seed, remove rest before seeding.

How and when to save seed

Use the wet method for plants like zucchini, tomato, pumpkin, and cucumber where the seed is inside a fruit. Cucumber and zucchini need to be left on plant until oversized and yellow. Leave them for a good month or so after picking time. Tomato and pumpkin seed are ready at the same time as the vegetable.

First, cut open the vegetable and remove seeds. Spread them out on a plate or tray to dry somewhere dry. Leave them until they are dry (depending on the weather a few days to a few weeks). You can put them in a bowl to continue drying once they are almost dry if you need the space. Make sure they are completely dry, because they can easily go mouldy.

Use the dry method for plants like silverbeet, lettuce, the Umbelliferous family (parsley, carrot, fennel, dill), the Brassica family (broccoli, kale, mustard), peas, beans. Wait till the seeds are dry or almost dry on plant. If they are almost dry and the seeds are dropping out at the top but not quite ready at the bottom, pick the stem and leave in paper bag to fully dry. Revolve from pods or husks by swirling around in a big bowl – the seeds are heavier and fall to the bottom and you can blow the husk away. This is called winnowing. Leave the seeds in a bowl to dry fully and for all the creatures that were living in the seed heads to leave.

Storing seed

Ideally, store seed in sealed, dry, airtight containers in the dark at a cool, steady temperature. It helps to have the seed well labeled with the year it was collected. A good way to store them is in groups of seed envelopes inside mason jars in a dark cupboard. You can also use zip lock bags. The freezer, fridge, basement, root cellar, or a cool closet all work well.

Pollination

There are 3 types of pollination

Self-Pollination: male & female parts within same flower (tomatoes,peas, bean, lettuce)
Insect Pollination: bees, hoverflies, and butterflies transfer pollen between flowers
- Monoecious – separate male and female flowers on same plant (cucumbers, pumpkins) & Dioecious – male and female separate plants
Wind Pollination (spinach, corn, beetroot, chard)

Cross Pollination

Varieties of the same species can cross-pollinate – when different varieties cross the seeds that they produce will lose their uniformity and distinct characteristics. For example broccoli and cabbage and will cross, they belong to the Brassica family, species is oleracea. They will not cross with Mustard (Brassica rapa) or rocket (Brassica eruca). Self pollinated crops are unlikely to cross pollinate. To prevent cross-pollination, a recommended isolation distance is required, or you can ensure they are not flowering at the same time or you can cover the flower and pollinate by hand.

In my experience, cross pollination is rare. I would recommend not worrying too much about the technicalities and giving it a go! The worst that will happen is your plant won’t produce properly. For example the ‘brocoli’ will never flower, or the ‘beetroot’ will never form a root.

Viable Seed

If seed is not collected from enough plants over time, the seeds may not remain viable – they wont produce or grow well. This is kind of like in-breading. In the table below, it shows how many plants you need to collect from for seed to be viable, and also, over time for seed to maintain it’s variety characteristics and preserve the genetics. For the home gardener the viability is the main thing to look at, but over many years of seed saving it is good to bring new genetics into the mix.

The best resource for seed saving is The Seed Savers Handbook by Micheal & Jude Fanton

Seed Saving Cheat Sheet

Family	Vegetable	Pollination	Viable Seed	Variety maintenance	Genetic Preservation
Apiaceae / Umbellifer	Parsely, Celery, Carrot, Fennel, Parsnip, Dill, Coriander	Insect	5	20-50	80+
Amaranthaceae (beets)	Silverbeet/Chard, Beetroot, Spinach	Wind	5	20-50	80+
Amaryllidaceae (Alliums)	Spring Onion, Leek, Onion	Insect	5	20-50	80+
Brassicaceae (Brassica)	Broccoli, Cabbage, Cauliflower, Kale, Mustard, Diakon, Radish, Turnip, Rocket	Insect	5	20-50	80+
Fabaceae	Beans, Peas	Self/insect	1	5-10	20+
Asteraceae	Lettuce, Chicory, Endive, Sunflower	Self	1	5-10	20+
Solanacea (nightshade)	Eggplant, Tomato, Capsicum, Chilli	Self/insect	1	5-10	20+
Cucurbit	Cucumber, zucchini, pumpkin	Insect	1	5-10	25+
Poaceae	Corn	wind	10	50-120	200+