Koanga’s Seed Saving Instructions

Koanga’s Seed Saving Instructions

See bottom of page for information specific to different plant families.

Seed Saving used to be one of the most important jobs there was – our ancestors survived because they saved the seeds that could be depended on to nourish people. Over the past 60 years we’ve left seed saving to the multinationals whose Kaupapa is to return money to their shareholders – rather than one of nourishing people.

Sixty plus years of saving seed to make maximum profits has changed our seeds, and I believe changed their ability to nourish us. When you breed a seed for sugar content, and production for many plant generations you change the nutritional make-up of that cultivar and inevitably make them less nourishing to us humans.
The only seeds we have today that have been bred for nourishing people, are our Heritage seeds. For those of us living in this land we have our very own New Zealand Heritage seeds that were bred by our own ancestors to actually nourish us.

We are the seeds – the seeds are us. It’s a wonderful journey learning to grow these seeds again, eating the vegetables, saving the seeds, connecting again to the stories and their whakapapa  –  our whakapapa, and knowing we’re keeping them there for the ones to come.

Making these connections is a wonderful way to heal and feel ‘whole’ again.
See the back cover for contact details and become a member of the Koanga Institute to support us saving the seeds of our own ancestors, to receive our catalogue and give your access to these seeds.

Seed Saving
If you’re new to seed saving and you’re planning to save some of your own seeds this Summer, then spend the Winter reading and re-reading this information and making a good plan. (full version is available as a printed brochure – Save your own Seed) Spend some time looking at the following charts, and maybe check out the Koanga Institute catalogue which also lists all the seeds in their families. It’s important to get a feel for which plants are in which families.

It will be possible for you to save your own seeds using the information here, however if you decide you’re going to get really serious about seed saving and want to know everything you can find, then I suggest you buy a copy of  Seed to Seed by Suzanne Ashworth. It is the book I learned to save seeds from and is the best book in the world as far as I’m concerned – easy to read and follow.

We are the ancestors; we are the human link between past and future. The seeds of our ancestors will only be available to nourish our grandchildren if we save them today. It’s up to us! It’s easy to see how hard or easy the saving of any particular line is by checking to see what has survived. The easy ones we have lots of – beans, tomatoes, garlic, peas and lettuces. The hard ones we struggle to find ones which have been saved – carrots, pumpkins, cabbages, cauliflowers, cucumbers. There is room for anyone to be involved at any level.
Basic seed saving can be done by everyone with no more than the basic info in this booklet.

Once you have read this entire booklet, have planned your garden so that you know what you will be growing for seed, and have grown the number of seedlings required to keep the genetic strength in the seed (again, use the info under the seed family info below), it is only a matter of growing the plants to the eating stage just as you would all your other plants in the garden.

Follow the rogueing/selection instructions for each family during this period, so you eat or remove plants where necessary. From the eating stage on, many plants will grow very tall. Sometimes the plants will become unrecognisable as a swede or cress plant etc., and you will have to take good care that they do not fall over.
We use frames that we have made with sheets of concrete reinforcing steel, bamboo or ti tree (see diagram 1) to hold the plants up. If you are going to use this method then make sure you plant the plants in blocks the width of a bed (1.2 m) which happens to be the width of a sheet of reinforcing steel, rather than rows, which will mean you have to stake them individually. It is critical to watch moisture levels in the soil when crops are going to seed, water stress will attract shield bugs and aphids etc.

We have had stands made that the reinforcing steel slots into at whatever height we need the mesh to be at. It would be easy to tie the mesh to poles at each corner of the bed, or even simply make bamboo frames around the bed and tie extra poles across the top of the frame to hold the plants up (see diagram 2). It is easy to lose a whole crop at this stage to the wind. If you are making a frame to hold plants up, keep in mind that some seed crops are loved by the birds – if you can build your frame in such a way that you can just throw some bird netting over later when the birds become a problem (or preferably just before), you will be making life easier for yourself.

We dry our seed in the plastic house where we raise our seedlings to begin with. Then, after we’ve threshed and cleaned it, we put it through the electric dehydrator, making sure we have the moisture levels low enough to make it safe to put the seed into the freezer to kill any potential pests before storing it. If you are using an electric dehydrator, make sure it’s one with a thermostat, and you can turn the temperature down to 30°C. Most cheap dehydrators in NZ are on 70°C and they can not be turned down. If you are saving seed for home use only, you will not really need an electric dehydrator, just put the seeds in the sun on the window sill or in the greenhouse until very dry.

Once dried, all of our seed is cleaned (threshed) by a combination of dancing on it, either in a barrel, on the concrete or even the hard dry ground on a tarp. Rich from Seeds of Change in Gila, New Mexico, connected me to the age old process of cleaning seed by dancing on it on the ground, and in the process singing or story telling the stories into the seeds.

A combination of dancing and rubbing is all most seeds need, as long as they have been dried to a crackly stage first. Some people use flails to beat the dry seed pods to extract the seed (see diagram). After that you can either tip the seed from one container to another in a breeze, or set up a small electric fan at one end of a sheet spread on the ground and tip the seeds in front of the fan. The best seeds will fall closest to the fan, and the rubbish/chaff furthest away. This is called winnowing.

After winnowing the seed we place all of our seed into the freezer for a minimum of three days to kill any bugs or eggs of bugs that might hatch at a later date and eat the seed! In a home garden situation this is not as necessary, however, it is a great idea. If you don’t want to freeze your seed, or are unable to, you might like to try putting some dried herbs or leaves in with the seed to repel the insects. In India neem leaves are used for this purpose, perhaps we cold use Ngaio, garlic, diatomaceous earth or woodash.

“The problem is that the diversity is disappearing, and we can’t
wait for the experts to take responsibility. That was part of what Seeds of Change was founded on, the principle that all of us
have to take responsibility for preserving what diversity we can.
We try to create the awareness that people have a real ability
to make a difference.”  Seeds of Change; Gabriel Howearth

Below is seed saving information for the different families of vegetables

Seed Saving for the Alliaceae Family (onions, garlic etc)

Seed Saving for the Amaranthaceae Family (leaf and grain amaranths)

Seed Saving for the Apiaceae Family (carrots, parsnips etc)

Seed Saving for the Asteraceae Family (lettuce, yacon, artichokes etc)

Seed Saving for the Brassicaceae Family (cabbages, broccoli, radish etc)

Seed Saving for the Chenopodiaceae Family



Common Name






silverbeet, chard, beetroot, mangel beet, sugarbeet



lambs quarters



Good King Henery







Pollination: Members of the Chenopodaceae family are wind pollinated

Isolation Distances: The pollen is light and can travel for up to 10 km. As with the brassicas, I have found you can grow them far closer if you watch your valleys, trees, shelter and where you plant things.

Minimum Numbers: Plant a minimum of 300 beetroot,, rogueing out the 100 least true to type to keep the line strong for the long haul.
We’ve been sent many variations on the chard/silverbeet theme, so it’s clear that this plant has been one of the real staples for our ancestors in this land. It’s also clear to me that not all species of this family need to have such large grow outs. I think beetroot, mangle beet, sugar beet, spinach and quinoa do need large grow outs, but silverbeet, orach and chard cultivars seem to have worked for over 150 years in this land with far less numbers. I would suggest a minimum of 6 for these cultivars.

When To Plant: Many members of this family, especially the vulgaris species, will not go to seed unless they have been grown through a Winter. It works best to plant the seed in late Summer, get them to full size before Winter, and they will seed strongly the following Spring/Summer. Other species in this family will go to seed well if planted in Spring.

Rogueing: With beetroot, sugar beet, mangle beet, quinoa and spinach take out the least true to type and eat. With silverbeet, chard and orach only save seed from strong true to type plants.

Support/Protection: All members of this family will grow tall and need support in a home garden situation to prevent losing seed . We use stakes for tall plants like silver beet, and grids for lower plants like spinach. birds love the mature seed so you’ll have to watch carefully and cover if necessary.

Harvest: Chenopod seeds come from their stems very easily so it’s critical to harvest before this stage or very carefully which is often difficult.

Threshing: Once again we dry the seed heads well in the greenhouse until crunchy, then place them on a cloth on the dry hard ground or in our barrels, and jump on them. After removing all the big stems we then winnow

Selection: You’ll notice that seeds in these species can vary on each plant in size enormously. Some of the large seeds are an aggregate of many seeds held quite strongly together, others are single seeds. They should all germinate well.

Seed Life Expectancy: All beet seeds will retain 50% germination under cool, dry, dark conditions for 6 years, spinach 50% germination for 5 years.

Seed Saving for the Convolvulaceae Family

Pollination: Not applicable for kumara.

Isolation Distances: Not applicable.

Minimum Numbers: 1 plant will be enough, but more would be better, you will notice – many subtle differences between plants and being able to save your seed tubers from a large population will help keep a strong line. Ideally over 100 plants.

When To Plant: Kumara are perennial vines that are propagated vegetatively, either by shoots from the tubers or cuttings from the tips of the growing plants. When placed in a warm, moist, but very free draining medium (in August), shoots form along the sides of each tuber, take root, can then be broken off with their new roots and planted straight into the garden. We plant our kumara in deep boxes with 8cm of compost below them and 8cm above.

Rogueing/Selection: Kumara commonly carry serious viruses, and growers who keep their own seed over the years need to develop a system for minimising this problem. Kumara with very dark patchy skin often have a virus, and it will affect their keeping qualities seriously.
Joseph Land, our kumara curator, minimises the problem by taking cuttings from the first tips that appear from the tubers each Spring (or  alternatively from the plants when they begin running), rooting them in a seed tray and then planting them out in a separate block. The tubers from this block are the ones to save for growing tupu the following Spring. This is the traditional method for keeping kumara healthy. It is well known that the strongest growing tips are the healthiest, and best places to collect virus free material.

Support/Protection: Not applicable.

Harvest: Harvest on a waning moon, keeping the tubers from each plant separate until you can see which plants have the best crops and these will be your seed kumara.

Drying: Dry well on the ground, turning them after 2-3 days of sun and then another day or so for the other side. Cover the kumara at night with the leaves that were cut off them, removing them before the sun comes out each day.

Selection/Storage: Select the big fat female tubers that have narrow ends rather than the long thin kumara with less obvious ends to the kumara for seed. Store the kumara in cardboard or wooden boxes or kete, keeping each kumara from touching another by wrapping in paper, or putting in layers of sawdust, or using layers of silver fern or bracken, which are fungal deterrents.

Seed Saving for the Cucurbitaceae Family

This family in its many and varied forms, has been feeding the world since the beginning of recorded history, possibly in every country of the world, in every culture both past and present.



Common Name



wax gourd (winter melon)



watermelon, citron



muskmelon, cantaloupe, honeydew, casaba, Armenian cucumber (snake melon), Asian pickling melon, pocket melon (vine pomegranate), vine peach (mango melon), rockmelon



jelly melon (African horned cucumber)



cucumbers (except Armenian cucumber & African horned cucumber)



Malabar gourd (chilacayote)



squash (vars – banana, buttercup, hubbard, turban, triamble, green chestnut, red kuri, crown)



squash (vars – green striped cushaw, white cushaw, wild seroria squashes, silver seeded gourds)



squash (vars – butternut, cupola, Chuck’s winter)



squash (vars – acorn, crook neck, scallopini, small striped and warted gourds, spaghetti, zucchini, Kamokamo, gem squash)



Hard shelled gourd



chayote (choko or vegetable pear)

Pollination: All members rely on insects for pollination, especially bees which will travel several kilometres. All members of the curcurbitaceae family will accept pollen from all other members of the same species. The pumpkins of progeny of uncontrolled crosses will bear little or no resemblance to those of the parents. Luckily there are several species and it’s possible to grow one pumpkin from each species and get a reasonable range without them crossing (i.e. you can grow 4 pumpkins each year, one from each of the pepo, moschata, maxima and mixta families, without them crossing). Traditionally the seed is always saved from pumpkins which set after the first few on each vine. The first few courgettes or the first pumpkins on a vine contain far less seed than those that set later.

Hand Pollination: If you’re saving seed, you can also hand pollinate pumpkins in 5 easy steps:

  1. Go out into your pumpkin patch in the late afternoon and look around for male and female flowers that will open in the morning for the first time. It is pretty easy to tell which ones are about to open, but if you are not confident then I suggest you mark those you guess will open in the morning when the sun comes out and then go out again in the morning to see if you were right; it won’t take long to get that right. Once you know what the flowers look like that will open in the morning, choose 2 male flowers for each female flower you wish to pollinate in the morning (it is easy to see which are female flowers because they all have very visible pumpkins behind the flower, whereas the males don’t). Use cellotape to tape up the flowers so the bees don’t get there before you in the morning, then mark each flower with a bamboo stake or similar so that you can easily and quickly find your flowers in the morning.

  2.  Go out in the morning with more cellotape and a fine paint brush.Firstly pick the male flowers by their stems, and carefully tear off all the petals so that you have only the stamen remaining that you can hold by the flower stem. Lay your stamens on a plate or container then find your female flower and gently peel off the celloptape so that the petals slowly open out exposing the stigma, on top of the style that the pollen travels down to fertilise the ovary in the pumpkin.
    If you are gentle you can simply hold the male stamen by the stem and gently tap pollen from it into and onto the female stigma, or you can use your brush to take pollen from the male to the female. Do this again with your other male flower.

  3. Once you have put your pollen onto the stamen, tape the flowers (petals) back up again so that no bees can gain entry to this flower whilst it is still in a receptive period (which is 1 day, usually only the morning).

  4. Place a tag or label or mark this pumpkin in some way so you know that it has been hand pollinated.

  5. Make sure you water your plants to increase your chances of pollination.

Isolation Distances: If you want to save your own seed, you’ll have to check out any neighbour’s gardens within bee flying distance as well. Each plant produces both male and female flowers. My experience shows that bees as well as wind, use valley systems to travel down, and I have found that sometimes different members of the same species can be grown relatively close without crossing when using these patterns. You will have to do your own research in your own environment!

Minimum Numbers: It is best to grow 6 plants of each cultivar to maintain genetic variability, rather than saving seed from only one fruit or vine.

When To Plant: For the best results you must plant your seed in late September/October, possibly early November to give the plants maximum time to mature.

Rogueing: Choose your best plants if you have many planted, select for health, vigour, taste. If you are concerned that some of your original seed may be crossed then rogueing before the flowers open is critical if you don’t plan on hand pollinating. You can actually see what the fruit is going to be like quite well before the flowers open. If you can see they are not true to type, pull the whole plant out now before the flowers open and the pollen from this plant ruins all the other seed.

Processing: Once you have your pumpkins and melons harvested, it is best to save them to fully mature for up to a month before taking out the seed. Pumpkins will be best to leave for a month, obviously melons a shorter time, and other things like cucumbers somewhere in between. Use common sense here. Traditionally, the seed for saving was taken from the best pumpkin/melon (maybe the best tasting or longest storing etc.) and it was selected from the middle of the cavity.

Fermentation: Rather than simply just collecting and drying the seed, you can put the seed into water for a day or two (stirring often) and then rub and float off all the orange flesh, gelatinous coating and rubbish that hangs on to the seed if simply dried. There is no real need to do this for home seed saving, but it does make for beautiful seed, and free flow seed if you are planning to packet it to share or sell.

Drying: You can then simply dry the seed until it snaps when bent and store (a window sill, dehydrator or greenhouse are good places to dry the seeds). Be sure you have a dehydrator that has a temperature control on it, so that you don’t cook the seed; never dry seeds over 35°C. Pumpkin seed goes mouldy very quicky if not dried well.

Seed Life Expectancy: Watermelon seed will remain viable for 6 years under cool, dry, dark conditions, rockmelons 5 years, cucumber 10 years, all squash and pumpkin 6 years.

Seed Saving for the Fabaceae (Leguminosae) Family

Pollination: Fabeaceae flowers are self pollinating, and do not usually cross within species or between species. However, there are some exceptions to this. In New Zealand, the coccineous species (runner beans) cross freely, as do Vicia faba (broad beans). I have also seen, and other seed saving organisations are saying the same, that there are some Phaseolus beans that also seem to readily cross. A lot of people get confused with ‘climbing beans’ and ‘runner beans’. Runner beans refers to the P. coccineus species (Scarlett runner family) which are climbing beans and cross very readily with other runner beans.

Isolation Distances: Isolation distances for P. coccineus are bee flying distances – it appears bees will travel far to visit these flowers, so it is important to keep them well isolated if you want to save the seed!  The other ‘climbing beans’ which are common are climbing varieties of P. vulgaris. These are self fertile and do not usually cross with other members of that species, although I have seen that a small number if the P. vulgaris species in our collection do seem to cross. There are also dwarf and bush varieties of P. vulgaris (also self fertile). Because they are self fertile, you can save seed from only one plant if necessary to keep the line going. Isolation is not usually necessary. Peas are self fertile and do not cross, so isolation distances are not necessary. Broad beans are pollinated by bees and insects and do readily cross, which means they need to be isolated by bee flying distance, which will depend on terrain.

Minimum Numbers: 1 plant will do (although it is better to save from more), except the P. coccineus and broad beans, where minimum numbers should be 16, preferably 32.

When To Plant: The best bean seed (vulgaris and coccineus and other warm climate warm season beans) will be saved from plants going into the ground when it warms in Spring (October or November). Cool season beans and peas are best planted in early Spring to achieve optimal seed crops.

Rogueing: Watch for signs of disease resistance, flavour, production, adaptability to your local conditions, and save seeds from the best. Eat the rest.

Support/Protection: Many beans and peas need support anyway just to harvest an edible crop, and broad beans sometimes need a string fence around the bed or something similar to prevent lodging, however  you may also have to keep birds off your pea crops to harvest the seed. We hang netting over the pea trellis’s.

Harvest: The easiest way is to be able to leave your beans and peas on the vines until they are crunchy dry.

Drying: If you are unable to do this they can be picked before fully dry and the drying finished in the greenhouse etc.; they must be crunchy dry to easily extract the seed.

Threshing: Beans and peas are the easiest to clean and the most fun, because the seeds are so beautiful. Tip onto the ground on a tarpaulin or into a cut off barrel (see diagram 3), and jump on them. The seeds come out easily and the pods can be simply removed by hand.

Winnowing: If you pick the barrel up at one end, about 20cm off the ground, and shake it, the seeds will all go to the bottom and the chaff will go to the top. Remove rough big chaff by hand then tip the seed from one container to another in the breeze to extract the remaining finer chaff. You can also rub the seed on a screen so that the finer chaff falls through. Beans attract weevils, so I always freeze my bean seed before storing.

Seed Life Expectancy: Runner beans will retain 50% germination if kept cool, dry and dark for 3 years, peas for 3 years, broad beans for 6 years, common beans for 4 years.

Seed Saving for the Gramineae Family

Pollination/Isolation Distances: Sorghums are generally inbreeding plants, which means they are self fertile, self pollinating and do not readily cross, although some crossing can occur. You can bag the flowers with squares of frost cloth or something similar tied loosely over the heads before the flowers open. You must leave room for the heads to get bigger.
Zea mays (corn) does cross readily. In areas where thousands of acres of corn are being grown and the pollen clouds are moving around high with the wind, there would need to be long distances between the varieties to keep them pure. However, we’ve found that it’s relatively easy in our gardens to keep the seed pure in quite small areas where attention is paid to planting in blocks rather than long rows, staggering planting times so the flowering is staggered, keeping a few metres between different cultivars, and collecting seed only from the middle of each block. Watch for bees however as some years the bees seem to actively harvest the pollen and this may cause cross pollination issues.
Rye is self fertile and does not cross with other varieties of rye, however all other grains do cross to some extent with other members of the same species. They are mostly wind pollinated so isolation distances will be determined by terrain, areas being grown, wind etc. Use common sense and see how you go. Staggering planting is very effective with grains as well.

Minimum Numbers: If you wish to save corn seed that will be strong for the long haul, you need to plant large blocks of around 200-500 plants. Save the best 100 cobs from the field – tag them at the eating stage, so they are left to dry on the plants. It is critical that you plant your seed corn in blocks rather than rows to ensure good pollination (see diagram 5). For sorghum you need only one plant, but preferably 16-32 plants to save seed from. We recommend with all other grain that you save seed from blocks of more than 500 plants.

When To Plant: The best seed will be from plants that have had the whole growing season to fully mature. Plant when the seed packet or catalogue tells you is the best time to plant that particular cultivar.

Rogueing: It is best to do your first rogueing with all grains, as you notice differences in the way the plants grow, or the colours in the leaves. If you see plants that stand way above the others or way below you need to decide if you would choose this variability or not. It may be a sign that the seed is crossed, or just a diverse population you could be keen to maintain.
Corn requires constant viligance to keep a line strong and pure. It varies a lot on colour, height, how much it tillers etc., and I always rogue to ensure I have an even looking strong patch. The next stage where you can rogue corn is at the sweetcorn or green stage. Selecting and marking only the best corn cobs for seed before picking the rest for eating is critical. I usually tie brightly coloured pieces of cloth on the largest and best looking cobs. If you are growing blocks of more than one cultivar then be sure to harvest or mark your seed cobs from the middle of the patch.
The third point at which you can rogue is when you harvest the seed heads/cobs. You can then go through all the seed cobs and choose the 50-100 best cobs. These cobs will contain genetic diversity from the entire population they have come from, but may  still vary a lot so choose the best  60-80 of them for your own special seed.
For corn the forth possibility for rogueing is when you remove the kernels from the cobs. I take a machete or heavy chopper and chop off both ends of every cob, to ensure I only collect the biggest and best kernels in the middle of each cob. Once you have the kernels from the middles of your best cobs all mixed up, you can then take out of that seed, the amount you actually need. Corn ‘runs out’ very fast if you do not follow all these steps every year. Genetic strength is absolutely critical with corn, making it difficult tomaintain seedlines in small home gardens!

Support/Protection: Corn needs no support or protection except from birds and rats in some cases; common sense is applicable here. Other grains may need support if they are being grown in BioIntensive beds. We put stakes around the outside of beds and tie string around to make a tight fence so the grain doesn’t fall over. Most grains will need bird netting placed over the grain as explained on page 5 to avoid losing your crop.

Harvest: Leave corn and other grains to dry on their stems as long as possible. If necessary harvest before fully ripe and place in greenhouse to finish drying. Maturing grain was traditionally stooked, harvested and left in the field for a few days/weeks to mature before threshing. When picking corn leave the husks on the cob until it’s very dry then you can remove the husks to finish drying the cobs. There are different ways the corn cobs can be managed. Some people leave the corn in the field until it is very dry, then simply pull off the outside sheaths covering the grain and then throw into a corn crib. The other way I’ve done it is to leave the cobs on the plants as long as possible, keep an eye on rat and bird damage, and then throw the cobs, after pulling off the sheaves, onto the wire rack in the greenhouse to fully dry.

Threshing/Processing: Most grains are very easy to thresh simply by placing when dry and hard, onto a tarp on the ground and dancing on them or using a flail to beat them. Once the corn seeds are really dry, you can put the cobs through the shucker and store the grain in a polypail. Leaving the seed on the cobs helps to keep the weevils out, as was traditionally done. Check out storage below if you plan on keeping your own seed.

Selection: For most small grain seeds you can use the selection instructions on page 7. For corn there is a little more to it. You have to keep your best 100 cobs separate to the rest of your cobs. Take off the husks (shuck them), then choose the best 70 looking of those cobs. Next organise yourself so that you have a good chopping board and a machete or chopper, and chop off both ends of each cob. If you look carefully you will see that on each cob the kernels in the middle are uniform; at each end they vary in size and shape. We cut these varying, usually small and unusual shaped kernels off so that they are not in the seed corn. The chickens get those kernels! The remaining cobs with all the kernels on them can then go through your corn shucker or you can remove the seed by hand and mix it. The mixing ensures you have genetic strength to keep that line strong.

Storage: For those of us growing corn in large enough quantities to make porridge, and use for chook food, bread etc., corn cribs (as our ancestors used to have) will probably be the easiest way to store it.

Seed Life Expectancy: Sorghum and sweetcorn will retain 50% germination for 4 years under cool, dry, dark conditions; popcorn, flour corn and dent corn will remain viable for far longer.

Seed Saving for the Portulacaceae Family

We grow two cultivars from this family: Miner’s Lettuce and Purslane.

Pollination: Miner’s lettuce is self pollinating and is not pollinated by insects; it does not cross with purslane. Purslane is also self pollinating.

Isolation Distances: Isolation distances are not required.

Minimum Numbers: Seed from 16-32 plants to maintain genetic diversity.

When To Plant: Purslane is a heat loving plant, so plant in October or November to collect the best seeds. Miner’s lettuce is a cold loving plant, so plant for seed either in Autumn (April in the North, maybe March in colder areas) or in early Spring.

Rogueing/Selection: Watch for variation and take out those that are weak or choose an especially good one for seed.

Support/Protection: Neither need any support as they are both ground hugging plants.

Harvest: Both of these plants drop their seed quickly, and on top of that the Miner’s Lettuce seed is very hard to see. I find it best to visit them both twice a week when they are flowering, to check what the seed heads look like, and harvest all heads that look as though the seed is darkening in colour onto a cloth. I usually harvest whole plants in the case of Miner’s lettuce because they have such a fragile connection to their roots that picking parts of the plant often breaks the connection.

Processing: The seed easily falls out of the seed heads onto the cloth as it dries in the greenhouse.

Seed Life Expectancy: Miner’s lettuce will remain viable for 5 years under dry, dark, cool conditions, purslane 7 years.

Seed Saving for the Solanaceae Family

Pollination: All species of the Solanaceae family are self pollinating. Bees are not attracted to these flowers but many other insects are, and a lot of crossing can occur.

Isolation Distances: Tomatoes are usually self pollinating and are not usually visited by bees, so isolation distances do not  usually matter. I have seen very little crossing (though others tell me they have). However, it is possible, and has been known to happen. If you are very concerned then isolate varieties by 10m with something growing in between them.
Peppers cross far more readily within species, and I would suggest you never plant hot peppers anywhere near sweet peppers if you are serious about saving seed. If I had a situation where blocks of 20 peppers of one variety could be 10m from another variety and there was a high block of corn (or similar) in between, then I think that would work between sweet peppers, but hot peppers need to be in another area, probably 30-50m away from any other peppers.  Eggplants cross with the melongena species and need to be in blocks for good pollination rather than long rows, but keep varieties 20-30m apart.

Minimum Numbers: 1 plant is enough, although more is better, to ensure you are saving seed from most true to type fruit, and that you are maintaining a wide genetic base. With eggplants and peppers it is best to have minimum of 16 plants. 1 potato plant is enough to save seed (because we save the tubers).

When To Plant: Eggplant and pepper seed needs to be planted in late August and early September to crop well over Summer and achieve best seed results. Tomato seed should be planted in September or October for best seed, potatoes can be planted any time there is 4-5 months frost free available after planting.

Rogueing/Selection: Peppers, tomatoes and eggplants: if you weighed the fruit that comes from each vine you could select for weight of crop. Decide exactly what you want to select for, as this will affect your seed and fruit/plant characteristics over time. Do you choose early fruiting, or disease resistance over the whole season etc.? Always be on the lookout for your best plants and mark them carefully as your mother seed plants.
Potatoes need annual careful rogueing to maintain strong true to type seed lines. All plants that appear for any reason at all to be not quite normal must be removed as early in the season as possible. Disease is spread in potatoes by insects such as aphids that are sap feeders, so ensuring rogueing is done early in the season makes a huge difference to the potential spread of disease.
The first rogue is done during or before the seed is planted. When you take your seed from the onion sacks where it was kept hanging all Winter under the eaves your shed etc., discard any seed that is rotten or feels very soft, or has potato tuber moth faeces hanging from the eyes. Place seed in trays to grow shoots 4 weeks before planting, which now that we have the psyllid in New Zealand must be before mid September.
The second rogue can be done at planting time. Any seed potato that has weak shoots, or shoots of a different colour, can be discarded. Once the potato tops emerge, any leaves that show crinkling, yellow streaks, stunted growth etc. must be removed. Once flowering begins you can rogue out any that have different coloured flowers or are weak plants.
Harvest time is your next opportunity to maintain strong true and productive seed. Harvest your plants individually and keep the crop that grew under each plant in its own pile. Once you have finished digging you can go along your lines and select the plants that have the heaviest best looking tubers; these are your seed tubers. The largest tubers will grow your best potatoes next year but you may choose to keep the egg sized potatoes as your seed because of the suitability of that size for planting.

Harvest: Watch for birds eating the juicy seed part out of tomato plants before you get to them; they may need to be picked a little early or netted. Peppers must be fully ripe and coloured up before harvesting for seed. Eggplant fruits must be left to fully mature until they go hard with yellowish skin before harvesting for seed collection.

Processing: With tomatoes I cut the top (the end that was attached to the plant) off the fruit and squeeze out the seeds with the juice that surrounds them. Leave this juice to go mouldy on top for 3-5 days, then add water and stir vigorously. The good seeds will sink and the poor seeds and the rubbish will float. Pour the rubbish off the top, add water and repeat until you have clean seed in the bottom of the container. I then tip the seeds into a sieve and bang them into the drier or a piece of absorbent paper. Make sure that the temperature of the dehydrator is able to be controlled and is lower than 35°C if you are using one. Once the seeds are dry, you can rub them between your fingers to separate the seed again. You can just squeeze the seed straight from the tomato onto toilet paper or newspaper and dry the seeds in the sun, that will work fine, but they are hard to separate and use this way.
Pepper seeds are easier. Just scoop them out of the peppers (be careful if they are hot peppers as the heat is concentrated at the top of the seed stalks, wear gloves if necessary). Place the seeds in a container in the sun, greenhouse, drier etc., and when crunchy, separate seeds and extraneous material, and store.
To save the seed of eggplants, leave the fruit on the plant until they are mature (they change colour) and hard before picking. Then chop them up and whiz in a blunt old blender with water. If you then tip this mixture into a jar and add water, the good seeds will sink and the weak seeds and rubbish will float. It can then be tipped off and the good seeds dried.
Potato seed is easy to save, as most of the work will already be done by the harvest stage. Simply choose your best large or egg size potatoes and hang up in an onion bag in the light to stop them sprouting, or in a sack in the dark and cool to stop them sprouting. Those that begin actively sprouting first in Spring are the early potatoes, the ones that want to be planted first and that grow better in the cooler season.

Seed Life Expectancy: Peppers will retain 50% viability after 3 years if kept dry, dark and cool, tomatoes will remain viable for 4-10 years.

Seed Saving for the Valerianaceae Family

Corn salad is the only member of this family that we grow to eat, and it’s a bit tricky because it drops all its seed on the ground very quickly after it matures. It also needs light to germinate so it’s a great self seeder.

Pollination: By insect.

Isolation Distance: We find keeping them 20m apart in the garden with tall crops between ensures no noticeable crossing.

Minimum Numbers: 32-64.

When To Plant: While still warm in Autumn

Rogueing/Selection: Watch for exceptional plants to save seed from, remove all weak plants.

Support/Protection: They don’t need anything except vigilance to ensure all seed doesn’t drop out on the ground before you harvest it.

Harvest: Take a sheet and lay it beside your cornsalad bed. Cut the plants from their roots and remove the entire plant into your sheet. In order to harvest the maximum amount of seed it is best to let the first seed drop, and harvest the plants to obtain maximum seed in the middle of its seeding stage.

Drying: Leave to finish drying in greenhouse. I put the plants on a fine meshed sheet on a shelf in the greenhouse and the plants dry and drop all their seed on the sheet.

Seed Life Expectancy: Unsure, but short lived seed.