Silkworm Eggs & Hatchlings
Peaceful Silkworm eggs are kept in cold storage, so your eggs will begin to hatch approximately
5 – 10 days after receiving them in the mail. During the colder months of the year hatching can
take longer than usual, if your eggs are a blue/grey colour and plump looking they are healthy
It is the warmth of spring that stimulates silkworm eggs to develop. Therefore, un-refrigerated
silkworm eggs naturally begin to hatch around July through till early August in the warmer parts
of Australia, and from August through till October in the colder regions.
Fresh mulberry leaf is the easiest and cheapest food for your silkworms. The alternative to
mulberry leaf is silkworm food (otherwise known as chow). The chow can be used to feed
silkworms at any time of year and is fantastic for people who cannot access a mulberry tree.
Please ensure you have adequate immature mulberry leaves to feed your hatchling
silkworms, or purchase chow from our store.
First Instar silkworms or ‘hatch-lings’ need fresh immature mulberry tips or chow to survive, as
they cannot chew the mature leaves well enough to grow and survive the first week of life.
New mulberry shoots continue to grow through the season, so pick leaves close to the growing
tips of the branches.
In Australia no diseases are present that kill hatch-ling silkworms. Therefore, if your silkworm
hatch-lings shrivel and perish, it is not caused by disease, but may be due to one or more of the
following: Dry chow or mulberry leaf that is too mature for the baby worms, pesticide/insecticide, direct heat, excessive moisture.
If you are unable to source immature leaf for your hatch-lings, please purchase silkworm chow. The chow can be frozen for use with future colonies once your silkworms are eating mulberry leaves.
Silkworm Care Instructions
Hatching and Hatch-lings
When your silkworm eggs arrive, place them in a warm spot out of direct sunlight in a snap lid container to
protect from ants and bugs.
To ensure the silkworm eggs do not dry out, leave them in the unopened snap lock plastic bag they arrived in.
Alternatively, the eggs can be removed from the bag, and a small piece of damp cloth can be placed in with the
eggs to increase humidity. If using this method, ensure the damp cloth does not contact any eggs directly or
cause water to pool on the bottom of the container.
A clear or opaque container is preferable as the eggs need both light and dark to develop (please see
our Silkworm Rearing Guide for more information)
Do not return eggs to cold storage, as the hatch-lings have begun to develop during shipping and will die if the
temperature is reduced again.
Check the eggs every day for hatch-lings and transfer any baby silkworms to a separate container with food.
Food & Hygiene
Do not place mulberry shoots in with the unhatched silkworm eggs as this does not assist with hatching and will
potentially cause mould.
When the 1st instar silkworms begin to hatch, place a small tender mulberry leaf or small piece of chow into the
container close to but not on top of the eggs.
Silkworms require much lower humidity than eggs so discontinue use of damp cloth once the hatch-lings have
emerged or remove the hatch-lings from the bag if using the sealed bag method.
Remove any condensation that develops with a paper tissue. If water comes in contact with the hatch-lings they
A clean fine tipped paintbrush can be used to lift and move the 1st instar silkworms onto the leaves if necessary,
toothpicks also work well or purchase specialized tweezers for lifting silkworms from our store.
Use immature mulberry leaf or chow exclusively until the Silkworms have shed their first furry baby skin and are
in their second instar, at this stage they will be able to eat more mature mulberry leaves, if possible chop the
leaves up finely for to begin with.
The best mulberry leaf for Silkworms are the large healthy soft bright green mature leaves – discard any leaves
with dry spots, mould or animal droppings.
Silkworms are more susceptible to disease if they eat low grade mulberry leaf (dry, brittle, brown spots), or if they
are fed mature and immature leaf interchangeably. It is best not to go back to really immature leaf once your colony is accustomed to more mature leaves.
If the silkworms are to be handled by either adults or children, ensure hands are washed and dried thoroughly.
Silkworms eat constantly (yes they eat at night), and will eat continuously if food is available. They only stop eating when shedding their
skin, you can tell they are shedding when they sit on the side of breeding container motionless with their heads
Cardboard boxes are the ideal Silkworm home as they can be replaced as needed and reduces washing of
plastic tubs. Clean your silkworms breeding container once a week minimum in the early stages (Instars 1,2 and
3). In the later instars the silkworms will need to be cleaned out daily.
Be mindful if your area has high humidity, as bacteria can grow in a silkworm colony under these conditions. In
humid conditions, change the box twice weekly (Instars 1, 2 and 3) and daily for the later instars. Keep a close
watch for mould development among the frass (droppings) and leaf scraps. To check, lift up the matted leaves
and frass and look beneath, if there is mould clean immediately. Lining breeding boxes with paper towel helps to
absorb moisture away from the worms.
If using a Terrarium or plastic tubs/trays, wash thoroughly with a fragrance free biodegradable soap once a week
(Instars 1, 2 and 3 and daily for the later instars, if using paper liners then once weekly for later instars) and dry
completely in the sun before returning the silkworms to their home.
During the hotter months of the year silkworm colonies may be less successful, reaching a smaller size prior to
cocooning and producing smaller cocoons and less eggs. The ideal temperature for silkworms is 27 degrees C.
At the cocooning stage it is important to provide an ideal place for the silkworms to spin. Children love to make
toilet paper roll stacks, and these can be placed against the inside of the box, the base of egg cartons are
excellent too. If the space allowed for cocooning is the correct diameter the cocoons will have a uniform shape
When the silkworms have finished spinning, remove all cocoons and place in a clean box. The cocoons can be
‘stripped’ of their support webbing. This helps avoid tangling when the moths emerge.
It is best not to handle the cocoons after they are placed in the clean box.
The cocoon stage, when the silkworm is a pupa within, lasts approximately 14 days. Check your cocoons daily
The moths do not eat, drink or fly away, although some males have been known to fly a small distance in search
of a female, subsequently its not necessary to put a lid on the breeding container.
Ideally the moths should be moved into a clean box lined with paper so they can mate and lay eggs away from
To allow simple egg collection, line the box with paper for easy removal.
The moths will mate directly after hatching. The females will then climb the walls of the box and lay their eggs.
The eggs are lemon yellow when laid, and will slowly turn a darker colour over a number of days. After 3-5 days
the eggs should be the dark grey blue of healthy fertilised eggs. Any eggs left yellow are not be viable.
It can be very helpful to the female moths if the males are removed to a separate box once mating is completed,
to allow the females to lay their eggs without over-mating.
The moths will all die naturally after the mating and egg-laying is over, they rarely live longer than a week and
sometimes only a few days.
Take the paper off the box, fold and place in a plastic storage container.
Around mid winter next year place the eggs in a sealed snap lock bag, return to the container and place in the
fridge in a position where they cannot become accidentally frozen.
Remove the eggs from the fridge 10 days before you require them to hatch.