Seed Saving Instructions

Taken from the Real Seed Catalogue website - please visit their website on www.realseeds.co.uk for further information and to see their collection of seeds to buy

Seed Saving Instructions

Seed-saving is easy. You'll get better seed than you can
buy, even from us. And you can keep your own varieties going for future
years. But .. . just as with growing the plants, there are a few key
bits of information you need to know to keep varieties pure. It's not
hard, you just need to know how to do it.

Kate has written a very fine leaflet as a MS Word Document,
explaining the basics of home seed-saving for each family of vegetables.

It is a bit densely-typed, because we wanted it to be
as cheap to photocopy as possible.

This is released here under a Creative Commons licence,
so you can copy and distribute it as much as you like - for example
at seed-swaps - providing you do not charge for it, or modify it, and
that you give us credit for writing it.

• Download this free Seed Saving
  Instruction Leaflet , nicely formatted for printing out neatly.
• You can buy an excellent book from the Books Page which is more detailed and has nice pictures.
• Read the text of our leaflet below on-screen:

BASIC SEEDSAVING FOR BEGINNERS

These
sheets are designed to be a very basic introduction to seedsaving.  
Hopefully they should help you to grow good quality pure seed that will
grow true to type for year after year.   Seedsaving is easy; people
have done it for thousands of years, in the process breeding all of the
wonderful vegetables that we eat today.   Only in the last century has
it been taken over by professionals.   With a little care you and all
your neighbours can grow better seed than you could ever buy; ideal for
your own conditions, with better germination,   and growing stronger,
healthier plants.  

The Secret of Saving Great Seed

You want healthy seed that is true-to-type and keeps well. You need to ask yourself these questions:

CROSSING

• Will these plants cross with any others?
• Is this a good thing, or a bad thing? (Usually bad)
• How does this happen? (Wind? Insects?)
• What can I do to control this?

POPULATION

• Do I need a minimum number to get healthy seed? (e.g. do they breed as group?)
• Or do the plants live on their own and self-pollinate?
• Have I chosen the best plants for seed?

SEED EXTRACTION AND DRYING

• Do I need to do anything special to the seed ?
• Is my seed well dried and well labeled?

The
answers are different for each vegetable. So look in the appropriate
section below, and you'll know what to do. Its all pretty easy but you
do need to look it up in each case.

If these sheets
encourage you to develop your seedsaving further, try & get hold of
one of the books listed at the end, which will cover all of the species
not listed here & give you fuller instructions for everything.

Happy seedsaving!    Kate & Ben (www.realseeds.co.uk)

All you have to do:

Broad beans

Broad
beans will cross with other varieties that are growing nearby.   So if
you want to keep your variety pure, you need to isolate them in some
way.    Theoretically you should aim for at least half a mile between
varieties.   In practice, in a built up area, fences, trees and houses
will all reduce insect flight.   This means you should have minimal
crossing even with beans much closer than half a mile so long as none
of your immediate neighbours are growing different varieties of bean.

In
an open situation like an allotment, you can physically isolate plants.
Broad bean pollen is transferred by insects working the flowers, but
the plants will also self pollinate, so if you can exclude insects at
flowering time, say by a covering of fleece, your seed crop will be
pure.  

The simplest method of all, if you are
growing a relatively large number of beans and you are not concerned
about achieving 100% purity (eg just for your own use), is to mark and
save seed from several plants in the middle of a block of beans.  
Insects are relatively unlikely to come from a neighbouring patch
straight to the middle of your patch, tending to work the outside
flowers first.   So by the time they reach your seed beans, the amount
of 'foreign' pollen remaining should be small.    Always keep seed of
strong, healthy plants and get rid of any that are not typical of the
variety ideally before they flower.  

Let your seed
beans mature and dry on the bush. The pods will turn dark drown, dry
& wrinkled. Then pick and shell them out.   Check that they are
really dry by biting on them.   If your teeth leave a dent, dry them
further in a warm (not hot) place with a good flow of air.    Broad
bean seeds should keep for several years, so there is no need to grow
plants for seed every year.

French and runner beans

It
is important to grow some bean plants specifically for seed, rather
than simply collecting the left-over pods at the end of the season.  
The plants should be good strong specimens, and any that are less
healthy looking or not true to type for the variety should not be used
for seed production.

French beans are
self-pollinating, mostly before the flowers open.   Despite this, they
can be crossed by insects with other varieties nearby.   The extent of
crossing varies by area.   If you are just saving seed for your own
use, grow your seed crop of french beans at least 6 feet away from any
other variety (12 feet if possible), and you are unlikely to have a
significant problem with crossing in the UK.  

Runner
bean flowers need to be 'tripped' by wind or insects before the beans
set, and are much more likely to cross with other varieties grown
nearby than french beans.   Ideally, to be sure that no crossing takes
place, seed crops of runner bean should be at least 1/2 a mile away
from any other varieties of runner bean.   Bear in mind, though, that
buildings, trees, and other barriers will limit insect flight patterns,
and if you are gardening in a town or built up area, you are likely to
have relatively little problems with crossing unless your immediate
neighbours are also growing runner beans.   If they are - or on an open
site such as an allotment - your only answer may be to try to persuade
your neighbours to grow the same type of runner.  

To
collect the seeds, allow the pods to mature fully on the plant until
they start to yellow and dry out.   In wet weather, collect the pods
individually as they get to this stage.   Then spread out somewhere out
of the rain with a good airflow until the pods are fully dry and
brittle.   Once they are dry, shell out the beans and dry further out
of the pods.   The beans should be dry enough that they break when you
bite on them, rather than leaving a dent.   Store in an airtight
container. If they are well dried, and stored in a cool dark place, the
beans will last around 3 years.

If you have problems
with weevils eating your seeds, put the sealed container in the freezer
for a week immediately after drying the beans; this will kill any
insect eggs before they hatch.   When you take them out, let the
container come up to room temperature before opening it, otherwise the
beans will absorb moisture from the air.  

Peas

Peas
are almost entirely self pollinating, only very occasionally crossing
with other plants. Set aside a section of row that is entirely for seed
production, and make sure you sow at a time that will avoid pea moth  
To avoid physical mixing up of the seeds, separate different varieties
of pea with another crop.   Check the row from time to time as the peas
grow, and pull up any plants that are weak or not true to type.

Let
the peas mature until the pods are brown and the seeds start to rattle.
If the weather is very bad, pull up the whole plants and bring inside
(for example hung upside down from the shed roof) once the pods start
to wither, to ripen and dry further. Once the pods are really dry,
shell the peas out.   Dry the shelled peas further in a warm (but not
hot) place, label with the variety and date, and store.

Aubergines

Aubergine
flowers are mainly self pollinated, but can be crossed by insects.   So
if you are planning to save seed, you should only grow one variety.  
Aim for 6 to 8 plants each year to maintain a variety long term.   For
100% isolation you need 50 feet between your seed plants and any other
aubergines.   If you are growing them in a greenhouse/polytunnel you
should be able to get away with a somewhat smaller distance.

To
get ripe seeds let the fruits mature well past eating stage.  
Purple/black cvs turn a muddy purple-brown colour, green/white cvs turn
yellowish.   Mark 1 or 2 early good fruits on each plant to leave for
seed, and then pick and eat later fruits.

To remove
the seed, cut into quarters lengthwise, avoiding the core, and pull
apart.   The hard brown seeds should be obvious.   Put the quarters
into a bowl of tepid water, and rub the seeds out with your fingers.  
You may need to pull them apart to get all of the seeds.   Add more
water, stir thoroughly, & wait a few minutes.   Good seeds will
sink to the bottom, leaving debris and poor quality seeds on the
surface.   Pour the debris off gently through a   sieve, then refill
with water and repeat a couple more times.  

Eventually
you will be left with good seeds in plain water.   Empty into a clean
sieve, shake to remove as much water as possible, and then tip on to a
plate and spread out well.   Put to dry somewhere warm but not hot, and
mix occasionally to make sure that they dry evenly and don't stick
together.   Aubergine seeds will keep up to 7 years if dried thoroughly
& stored in a cool dark place.

Sweet peppers and chillies

Sweet
peppers and chillies are both members of the same species, Capsicum
annuum (some less common chillies come from other capsicum species).

Pepper
flowers are self pollinating, and will set fruit without any insect
activity.   However, they will also cross readily, and sweet peppers
will happily cross with chillies.   You need to isolate your plants by
around 150 feet (50 metres) from any other peppers or chillies growing
nearby.   Even if you are only growing one variety be careful about
other varieties growing in adjacent gardens or allotments.  

If
you want to grow several varieties, or if your near neighbours are also
growing peppers, you could consider making an isolation cage to cover 3
or 4 plants.   This is easy to do, and costs very little, especially if
you can get hold of some old net curtain material.   You can put a cage
up over plants grown in pots, growbags or directly in the ground.  

To
save the seed, take peppers on your isolated plants which have ripened
fully to their final colour (usually yellow or red).   Cut the peppers
open carefully, and rub the seeds gently off of the 'core' onto a
plate.   Wear rubber gloves to deseed chillies, as the chilli oil
sticks to your fingers and is very hard to wash off.   Dry the seeds in
a warm but not hot place until they snap rather than bending

Making an isolation cage

To
make a simple isolation cage ideal for peppers or aubergines,   you
need some cheap nylon flyscreen 5 times as long as it is wide, four
canes or thin stakes, and some string and garden wire.   Alternatively,
you can use old net curtains, or other netting small enough to exclude
insects.   A piece of screen 1m by 5m will give a cage large enough to
cover 3 or 4 plants.   

Cut a square piece of screen
1m x 1m to make the top of the cage, and then fold the remaining strip
of flyscreen round and sew its ends together. The resulting band will
be the sides of the cage. Then sew the top to the sides, making a cube
of flyscreen with the bottom missing.  

To put up the
cage over your plants, hammer the four canes into the ground in a
square a little smaller than the cage top, so that they stick up a
little less than the height of the cage.   Twist a short piece of wire
tightly round the top of each cane, and then run string in a square
around the tops of the canes, supported by the wires to stop it
slipping.   Run a second piece of string around the stakes lower down
to stop the sides of the cage blowing in against the plants.    Then
slip the cage over your plants, and weigh it down with earth or rocks.

Tomatoes

Most
modern varieties of tomato are self pollinating, and will not cross.  
The anthers on tomato flowers (which make the pollen) are fused
together to make a tight cone that insects cannot enter. Usually the
stigma (the receptive surface for receiving pollen) is very short, and
so is located deep inside this cone of anthers. No insects can get to
it and the only pollen that can fertilise it comes from the surrounding
cone of anthers.

In a few varieties however, the
stigma is much longer, sticking out beyond the cone of anthers. In this
case, insects can get to it, and there is the chance of
cross-pollination.   Varieties with longer stigmas include potato
leaved tomatoes and currant tomatoes.   To avoid crossing only grow one
variety with exposed stigmas.   The double flowers which are sometimes
formed first by many beefsteak tomatoes also often have exposed
stigmas, but later single flowers will be normal.  

To
collect the seed, allow your tomatoes to ripen fully.   Then collect a
few of each variety that you want to save seed from.   Slice them in
half across the middle of the fruit, and squeeze the seeds and juice
into a jar.    You then need to ferment this mixture for a few days -
this removes the jelly-like coating on each seed, and also kills off
many diseases that can be carried on the seeds.   To do this put the
jar of seeds and juice in a reasonably warm place for 3 days, stirring
the mixture twice a day.   It should develop a coating of mould, and
start to smell really nasty!

After 3 days, add plenty
of water to the jar, and stir well.   The good seeds should sink to the
bottom of the jar.   Gently pour off the top layer of mould and any
seeds that float.   Then empty the good seeds into a sieve and wash
them thoroughly under running water.   Shake off as much water as
possible, and tip the sieve out onto a china or glass plate (the seeds
tend to stick to anything else).   Dry somewhere warm but not too hot,
and out of direct sunlight.   Once they are completely dry, rub them
off the plate and store in a cool dry place, where they should keep
well for at least 4 years.  

Beetroot, chard & leaf beet

Beetroot,
leaf beet/perpetual spinach, swiss chard & sugar beet are all
members of the same family & will cross readily.   They are
biennial, and flower in their second year.   Chard/leaf beet for seed
are overwintered in situ, and will be fine in most of the UK.   Select
a minimum of six to eight plants to leave for seed which best fit your
needs (depending on your preference for stem versus leaf, smooth or
wrinkled leaves etc).   Beetroot can also be overwintered in situ, or
can be harvested in autumn, the best plants selected & stored then
replanted in spring.  

All types of beet will cross
with one another, and since the flowers are wind pollinated, crossing
can take place with any other flowering beet plants within around 2
miles.   How fussy you need to be about crossing depends on what you
are trying to achieve.   If you simply want a reasonably diverse
population of leaf beet, a degree of crossing is not that important.  
Plant your seed plants closely together in a square, and take seed from
the central plants in the block; you will find that the amount of
'contamination' is minimal providing there aren't large numbers of
other flowering beets right next door.

If you are
aiming to keep a variety true to type you need to isolate it, usually
by physically covering your seed plants.    To do this, plant at least
six plants very close together in a circle, with a wooden stake in the
middle.   As the seed stalks form, growing up to four feet tall, tie
them together, supported by the stake.   Then as they develop cover the
group of flower heads with either a shiny paper bag that will withstand
rain, or a bag made out of agricultural fleece.   Shake the bag from
time to time to make sure that pollen is distributed within the bag.  

As
the large, prickly seeds mature, keep an eye on them, and start to
harvest as they turn brown and start to dry out.   You can either cut
entire seedstalks, or harvest mature seeds by rubbing them into a
bucket.   Make sure that the seeds are thoroughly dry before storage,
and they should last at least five years.  

Carrots

Carrots
are biennial, flowering in their second year of growth.   In areas with
mild winters, leave your carrots in the ground, mulching them heavily.
The foliage will die back in autumn, but will then resprout and start
to flower in the spring.   In colder areas, dig up your carrots in the
autumn, and select the best coloured and shaped roots.   Twist off the
foliage, and store the roots in a box of dry sand in a frost free
place, making sure that they don't touch.   In spring, replant the
roots, and they will resprout and flower.  

If you
want to maintain a carrot variety effectively, you really need to  
save seed from at least 40 good roots to maintain good genetic
diversity.   If you have too small a genetic pool, you will end up with
small, poor quality roots in a very few generations.  

Carrots
grow into big plants waist high or taller, producing successive
branches with large flat umbels of flowers.   They are insect
pollinated, and need to be isolated from other flowering carrot
varieties by at least 500m in an open field situation.   This is not
normally a   big problem, since few people let their carrots go to
seed.    However, they will cross with wild carrot (Queen Anne's Lace),
giving thin white useless roots.   As with all insect pollinated crops,
barriers such as houses, tall hedges and other high crops can affect
insect flight paths drastically, so you don't necessarily need to
eliminate all Queen Anne's Lace within a 1/2 km radius; but do watch
out for any white roots in subsequent generations and get rid of them.

To
harvest your carrot seed, keep an eye on the umbels of flowers, and cut
them off with secateurs as they start to turn brown and dry.   If you
have plenty of plants, just save seed from the first and second umbels
of flowers to appear on each plant, as these will give the biggest and
best seed.   Dry the seed heads further inside, and then rub them
between your hands or in a sieve to separate them.   You will notice
that the seeds have a 'beard' which is removed in commercial seed to
make them easier to pack.

You can sieve the seeds
further to remove more of the chaff, but there is no need to get the
seed completely clean - just sow slightly more thickly to allow for the
chaff mixed in.    Carrot seed is relatively short lived, but if it is
stored somewhere cool and dry, it should give good germination for 3
years.  

Some common herbs

Basil, coriander and dill are annuals, parsley is a biennial, flowering in its second year of growth.

Basil
flowers are insect pollinated, and different varieties flowering within
around 150' of one another may cross.   On a garden scale, if you want
to grow several types of basil, just keep picking the flower stalks off
of all the varieties apart from the one that you want to grow for seed.
Once several flower spikes have set and the flowers have started to
wither, mark those spikes for saving seed from, and you can then allow
the other varieties to flower.   The seeds are ready to collect when
the spikes turn brown and dry out.   Don't worry about the seeds
dropping out - they are well attached, and actually need quite a lot of
rubbing to free from the dead flower heads.

With both
coriander & dill, to get the best seed for sowing in future years,
pull up and discard the earliest plants to bolt, and only save seed
from those plants that produce plenty of leaf and flower late.   It is
best to plan to save seed from early summer sowings, to allow plenty of
time for the seed to mature and dry on the plant.   Harvest as soon as
the seed is brown and dry, as it does tend to drop from the seed heads.
Rub the heads together in your hands over a bucket to free the seed.
Dill seed usually comes cleanly away from the seed heads.   Coriander
seed tends to contain more chaff, but you can winnow it by pouring
gently from one bucket to another in a light breeze if you want to
clean it for kitchen use.

To save parsley seed,
overwinter at least two or three plants.   In warmer areas mulch
heavily with straw or cover plants with a frame, elsewhere grow a few
plants in a polytunnel or greenhouse.   The next spring, the plants
will start to flower and produce seed.   Flat and curly leaved
varieties will cross, as the flowers are insect pollinated, so you
should only grow one type for seed at a time.   Harvest the seeds from
individual flowerheads as they dry and turn brown, as they tend to drop
from the plant when ready.  

Broccoli, kale and cabbages

Sprouting
broccoli, cabbages, cauliflowers, calabrese, kales and brussels sprouts
are all members of the same family (Brassica oleraceae), and will all
cross with each other.   They won't cross with turnips, swedes,
oriental brassicas or mustard greens.   In addition, they are mainly
self-incompatible - which means that in order to get seed, insects have
to carry pollen from one plant to another to pollinate the flowers.  
Because of this, you can't simply grow your broccoli or cabbages for
seed in an insect proof cage to avoid crossing.    

So
long as you only seedsave from one member of the family in any given
year, you can grow as many other brassicas as you like without problems
so long as you don't let them flower.  

For absolute
seed purity, make sure that there are no other flowering brassicas
within a mile of your garden.   In practice, fences, trees and tall
crops all break up insect flight patterns, so as long as you don't have
any immediate neighbours with flowering crops in their garden, you
shouldn't have too many problems with crossing.   To make it as easy as
possible for insects to work your seed plants, make sure that they are
laid out in a block, rather than a row, so that bees tend to move from
one plant to another, rather than away to other flowers elsewhere.

Keep
at least six plants for seed, ideally more. Remove any poor specimens,
or any that are not typical for the variety -you can always eat these
plants, so long as you don't allow any flowers to open.  

All
of the brassicas, including cabbages, will throw up a tall flower stalk
covered in lots of small yellow flowers.   These will then form slender
seed pods, which start out green, and turn a straw colour as they
mature and dry.   Once they start to dry, keep a close eye on them, as
they tend to shatter and drop their seed.   Its best to cut entire
plants once most of the pods begin to look dry, and then leave them to
mature further on a sheet indoors.   Once they are thoroughly dry, the
seeds will come out of the pods very easily; the simplest way is to
trample the plants on top of a large sheet, and then sieve out the
debris.  

You should get lots of seed from even a few
plants.   The seed will keep well for up to five years so long as it is
stored somewhere cool and dry.  

Turnips and the oriental brassicas

Mizuna,
pak choi, tatsoi and mibuna are all sub varieties of Brassica rapa -
the same family as turnip.   This means that although they will cross
with each other, or with turnips in flower, they won't cross with
broccoli or cauliflowers.   Although you can only grow one of these
vegetables for seed in any year, you can of course grow any of the
others for kitchen use, so long as you don't allow them to flower at
the same time as your seed plants.  

To grow an
oriental brassica or turnip variety for seed, you usually need to
overwinter the plants.   They are naturally biennials, producing their
flowers and seeds in their second year of growth.   Although spring
sown crops may bolt to seed in hot summer weather, this is not ideal
for seedsaving, as you may end up accidentally selecting for early
bolting in future years.   The best solution is to sow your seed crop
after midsummer in a polytunnel, where semi-mature plants will
overwinter quite happily in all but the coldest parts of Britain.   If
necessary you can give extra protection in cold weather by putting
fleece over plants inside the tunnel.   Select at least 6 of the
healthiest and most typical plants to reserve for seed, eating the rest
over the winter.   In spring, the plants will flower, and then form
seedpods.   Make sure that there is good insect access to the tunnel at
this point so that the flowers are pollinated.

The
seedpods are green at first, but then gradually dry out and turn a pale
tan colour.   Once most of the pods are dry and brittle, cut the entire
stalks of the plant, and lay out on a sheet somewhere undercover with a
good airflow to finish drying off.   Then rub and crush the pods with
your hands to release the seeds, and separate the seeds from the chaff
with a coarse sieve.

Lettuce

Lettuce
flowers are self pollinating, and very rarely cross.   If you plan to
save seed from more than one variety of lettuce, separate them by
around 12 foot or plant a tall crop in between the rows.

Select
two or three good lettuces from your row, and mark them for seed.   It
is very important not to save seed from any plants that bolt early, as
you want to select for lettuces that stand well. Heading lettuces may
need a little help for the flowering stalk to emerge;   slitting the
heads partially open with a knife works well.  

Once
the lettuces have flowered, the seeds will ripen gradually, starting in
about a fortnight.   Harvest seed daily to get the maximum yield,  
shaking into a bag.   Or wait until a reasonable number of seeds are
ready and then cut the whole plant.   Put it head first into a bucket,
shaking and rubbing to remove the seeds.   If you leave the whole cut
plant upside down in the bucket somewhere dry, slightly immature seeds
will continue to ripen over the next few days.  

Most
of what you have collected in the bucket will be white 'feathers' and
chaff.   To sort the seed, shake it gently in a kitchen sieve.   Some
seeds will fall through the sieve, with the rest collecting in the
bottom.   The feathers and chaff will rise to the top, and you can pick
them off.   There's no need to get the seed completely clean; a little
chaff stored and planted along with the seeds won't cause any harm.

If
the seed feels a little damp, dry it further on a plate before
labelling and storing.   Lettuce seed should keep for around 3 years,
provided it is kept cool and dry.  

Pumpkins, courgettes, marrows and squashes

Beware
that pumpkins, squashes, marrows & courgettes will all cross
readily with each other.   The best (usually only) way to save pure
seed on a home scale is to hand pollinate one or more fruits.   This is
very easy & will avoid disappointments with lumpen squash/courgette
crosses.   The explanation given here is for pumpkins, but applies
equally to squashes, courgettes & marrows.

Pumpkin
plants have two different types of flower, male and female.   The
female flowers are the ones that will grow into pumpkins. They can be
identified by the small immature fruit which should be obvious beneath
the flower.   Male flowers just have a straight stem.   You need to
transfer pollen from a male flower into a female flower, making sure
that no pollen gets introduced from plants of a different variety.

One
evening, when the plants are just beginning to produce flowers, find
some male and female flowers that are going to open the next day. Buds
that are just ready to open are much fatter than the others, and they
have turned from green to yellow.

You need to stop
these flowers opening, so that insects can't get into them.   The
easiest way to do this is to gently slip a thin rubber band over the
end of the petals, to hold them shut.  

The next
morning   go back to the plants.    Pick a male flower, take off its
rubber band, and tear off the petals.   Gently take the rubber band off
of one of your female flowers.   Using the male flower like a brush,
rub the pollen on to each section of the stigma in the centre of the
female flower.

Then carefully rubber band the female
flower shut again so that no insects can get in with more, 'foreign',
pollen.   Tie a piece of wool loosely around the stem of the female
flower, so that at harvest time, you know which pumpkins you have hand
pollinated.  

Now leave the pumpkins to develop and
ripen. After you have harvested them, keep them in a cool   dry place
for another month or so to ripen further indoors.

Then
cut the pumpkin in half, and scoop out the seeds, leaving the rest of
the fruit for cooking as normal.   Wash the seed in a colander, rubbing
it between your hands to get rid of the fibres, and then shake off as
much water as possible.

Spread the seed out on a
plate to dry.   It needs to dry as quickly as possible, but without
getting too hot, for example on a sunny windowsill. To test whether the
seeds are dry enough, try bending one in half.   If it is dry, it will
snap rather than bending.

Melons & cucumbers

All
varieties of melon will cross.   Ideally, you need around a quarter of
a mile between different varieties.   If your melons are in a
greenhouse or tunnel, you can probably get away with a somewhat smaller
distance, particularly if there are hedges, houses or other tall
barriers in between your melons and the neighbouring crop.    Cucumbers
won't cross with melons, but will cross with any other cucumbers or
gherkins nearby.   Again, you need around a quarter mile isolation to
make sure that your plants won't cross.  

It is
possible, although fiddly, to hand pollinate both melons and cucumber
flowers.   Grow plants under a fleece tunnel to exclude insects, and
then hand pollinate the flowers on those plants with a paintbrush.  
Make sure that you exchange pollen between different plants to keep the
diversity of your variety.  

To harvest melon seed,
pick the melons when they are ripe and ready for eating and keep
indoors for a further day or two for the seed to mature further.   Then
open the fruit, scoop the seed out, and wash in a sieve under running
water.   Spread out on a china plate to dry thoroughly.  

Cucumbers
need to be ripened well beyond the edible stage.   They will become
much fatter, and green varieties will turn a dark yellow brownish
colour, white varieties a paler yellow. Keep for a week or so after
picking to let the seeds mature fully.   Then cut open, scoop out the
seeds and surrounding pulp into a jamjar, add a little water and stir
well.   Leave the jar on a sunny windowsill for 2-3 days for the seeds
to ferment.    On the third day, fill the jar fully with water, and
stir well again.   The good seeds should sink to the bottom of the jar,
leaving pulp, debris and empty seeds floating on top.   Gently pour off
the water and debris, refill the jar, and repeat.    After a couple of
rinses, you should be left with good seeds at the bottom of a jar in
clean water.   Drain off the water, and spread out on a plate to dry
well.

Both melon and cucumber seeds will last for several years if dried well and stored somewhere cool.  

Some useful references

"Back
Garden Seedsaving" by Sue Stickland (ISBN 1899233091) is an excellent
reference with a good intro to seedsaving plus details about each
individual crop.

"Seed to Seed" by Suzanne
Ashworth.(ISBN 1882424581) tells you simply and clearly what you need
to do to save seed of any veg you care to mention using materials you
have at home.

"The Seed Savers Handbook" Jeremy
Cherfas, (Grover Books, 1996) is also good and also talks in more
detail about the reasons that you might want to save your own seeds.

"Breed
your own Vegetable Varieties" by Carol Deppe ( Chelsea Green Pub Co;
ISBN: 1890132721) is a good introduction to vegetable breeding for the
interested amateur. Until 50 years ago, all gardeners were plant
breeders - it's not difficult, you just need to know how to do it, and
the tradition has been lost. This book will give you the basics, and
then if you're interested, the nitty-gritty too.