Monarch butterflies

are recognised globally as an endangered species

In the America's, the winter hibernation locations of Mexico and California are rapidly shrinking due to deforestation, harsh weather, development and other habitat disruptions. Because monarchs gather only in a few locations, the overall population is at risk. The biggest threat is climate change.

Our breeding program

Each year Sacred Blessing Sanctuary Garden breeds 1000-2000 monarch butterflies to add to the local population. The monarch butterflies can be seen in the garden predominately from November to March each year.

Life Cycle



Females lay about 300-400 eggs in their lifespan (about 40 per day). They lay eggs on the underside of a milkweed leaf. The eggs attach with a special glue like substance. As the larva develops, the egg changes in colour. The egg is grey when it is about to hatch and the black head of the baby caterpillar is visible. Hatching occurs in 3-5 days. They eat their way out of their eggshell, and eat the shell, which is full of protein.


11 - 18 DAYS TO GROW

The baby caterpillar spends its time eating plants in order to grow. In 11-18 days, the caterpillar grows about 2,700 times its birth weight. Its main food source is the milkweed species of plants.

The caterpillar moults five times through it growing stage. As it grows, it becomes too big for its skin (exoskeleton) so it moults (sheds) its skin.



After the caterpillar is fully grown, it will find a sheltered place to attach itself in an upside down "J" shape. It will then start the process of metamorphosis, that is, transforming from the caterpillar into the butterfly within the chrysalis, which can take 8-14 days (depending on temperature). Within the chrysalis, the caterpillar dissolves into a soup-like fluid, then reforms its cells into the structure of the butterfly.



The monarch butterfly will emerge hanging upside down from the pupa with an enlarged abdomen that is full of fluid. By hanging downwards, gravity will help the butterfly pump the fluid from the abdomen into their wings. This allows the wings to expand and dry so the monarch can use them to fly.

Monarch butterflies typically live 2 to 6 weeks during the summer months, except for the last generation of the season. As temperatures cool (with winter approaching) the monarch butterfly migrates to its wintering location. This butterfly can live up to 9 months during the winter hibernation period. After it's winter hibernation, it emerges, migrates to it's summer location, and the incredible cycle starts all over again. 

Other interesting facts


The female have thicker black webbing (veins) within their wings, and darker abdomens that are shaped differently. The males have two black scent glands (spots) at the centre of the hindwings to attract females. The black spots make identifying males and females easy. 


Any garden plants rich in nectar will attract monarch butterflies. However, it is the milkweed family of plants (the Asclepias genus), and most notably the plant commonly referred to as the Swanplant, that the monarch butterflies use as a host plant for the laying of their eggs, and also as their food source in their caterpillar form. It is commonly referred to as the Swan Plant, due to the shape of the plant's seed pod.


Monarch butterflies in New Zealand do not follow the same migration pattern of their northern relatives. They have adapted their migration behaviour to suit local conditions. When the air temperature drops to 12.8 degrees Celsius - 55 F (around April or May), monarchs flock together in over-wintering sites. It is assumed there are wintering sites on Waiheke Island. When the temperature warms up, the wintering butterflies emerge and reproduce.


Pests of the monarch butterfly include the brown soldier bug, praying mantis and wasps. To protect the caterpillar from these pests, at Sacred bLessing Sanctuary Garden we use two netted nurseries to keep them safe from being eaten.