Cockroaches
life cycle: 3 distinct stages:
- egg
- nymph
- and adult.
Egg Production
Adult females produce between 10 and 40 eggs at a time.
Shaped like a kidney bean, the egg case is either carried by the mother or placed in a protected location until hatching, preferably near a food source.
Nymph to Adult
Newly hatched cockroaches emerge as nymphs. The insects grow by shedding their skin multiple times until reaching adulthood, (molting)
After Molting
Cockroaches now become soft-bodied and white before eventually getting larger, getting darker in colour and hardening off.
In favourable conditions, cockroaches can reach adulthood in a matter of weeks.
Aphids
eat sap (sugar), then excrete it on the plant. 
The infested plant quickly becomes sticky.
Sugar-Loving Ants look after some Aphids because they have a guaranteed sugar source. They even carry them from plant to plant.
In exchange they protect aphids from predators and parasites.
Aphids Have lots of Enemies because they are slow, plump & sweet. A single plant can host hundreds or even thousands of aphids – a real smorgasbord for predators.
Aphid eaters:
- lady beetles
- lacewings
- minute pirate bugs
- hoverfly larvae
- big-eyed bugs
- damsel bugs
- and certain stinging wasps.
Aphids use alarm pheromones to warn nearby aphids. Chemical signals are released, sending nearby aphids running. Aphids are expert kickboxers, pummelling with their hind feet. If all else fails, aphids stop, drop & roll off their host plant.
Female Aphids Can Reproduce Without Mating
Females carry developing young, which themselves already carry developing young. This shortens the development cycle and increases population numbers rapidly.
Aphids give birth to live young. Eggs develop as soon as ovulation occurs, without any fertilization.
What to do about them in your garden? Check these links:
Cockroaches: https://youtu.be/HgliFGNmQps
Aphids: https://youtu.be/TJsHpCVg3TI and https://youtu.be/Jpmfz7C5bXo
Vera
President
Permaculture Sydney West