Titan arum bud dec 22 14 1aa



The largest of our three new titan arum corms has a bud that emerged from the soil on May 4, 2015. This corm weighed approximately 34 kg when it arrived at the greenhouse. On May 8, the bud was 17.8 cm high and 22.9 cm in circumference.

It’s a flower bud! On May 18th, the bud was 76.2 cm tall. The flower bud is growing 12.7 cm per day and was 1.09 metres on May 21st.  On May 29th, the flower bud was 1.83 metres tall, growing at a rate of 5.08 cm per day. That’s 6 feet! The flower has stopped growing. This means that the flower will bloom in a few days.  The flower bloomed on May 31st, 2015 and was named Magnus. 

Take a look at our twitter and on our facebook page for pictures.

unnamedTitan arum on May 8th.

unnamed2Titan arum on May 14th.

Titan arum on May 18th.

unnamed3Titan arum on May 25th.

CGVJdS8WgAAZ_rvMagnus in bloom on May 31st.


Phoebe was the first cultivated titan arum to bloom at a Canadian University. Also it was the first cultivated titan arum to come into flower anywhere in the world in 2015.

She was 5 feet 6 inches tall. The spathe unfurled overnight from January 4 to January 5, 2015. She closed up overnight on January 5 and the spadix collapsed over the weekend on January 11. Phoebe was dissected on January 12 and split into piece, measured, pollen was collected, their biomass determined, and other pieces will be used for molecular research.

Here are pictures of Phoebe from different life stages, as well as pictures of the spadix collapse and plant dissection.


Back in October 2014, the Biology Greenhouse procured and planted 3 Titan arum corms; 2 weighed ~23 kg (50 lbs) each and the other 34+ kg (75 lbs)!

Many changes happened in the Greenhouse once we decided to acquire the Titan arum. Since the plant needs a large pot and can be many meters tall, we had to clear out one of the beds. It took a lot of work and many plants had to be moved in the process.

This is what the bed looked like before, during and after:


As of late November 2014, one of the corms began emerging from dormancy. On December 22, 2014, the bud was 30 inches high and 16 inches in circumference. That day, Art, our greenhouse manager, was able to identify the developing growth as a flower bud.


A reinforced shipping container, measuring 1.2 metres shipping box 1aby 0.9 metres (4 feet by 3 feet) arrived at the McMaster Biology Greenhouse holding our 3 corms. The corms had left Gilford, New Hampshire, USA by tractor trailer heading to Canada. The exterior side of the container held all of the legal documents including the phytosanitary certificate. Canadian Customs inspected the shipment including all of the documents and then allowed the shipment to proceed on to the University. The total weight of the container was 181 kg (400 pounds). It was delivered from General Receiving to the Biology Greenhouse by a front end loader.

After removing the lid of the shipping container, the inside was filled to the top with packing material. The corms were buried deep inside and well protected from any damage. When the lid was removed and heavy odor of spoiled salt and vinegar potato chips filled the air. Since the Titan arum is the smelliest plant on earth, its corm also emits a very strong repellant odor even wrapped in bubble plastic and buried in packing material. It took the better part of an hour to safely remove the corms from the packing material inside the shipping container.

wrapped corm 1d

This is one of our corms (the one currently in growth), right out of the shipping container. It is wrapped in multiple layers of bubble wrap to protect the corm from damage. Titan arum corms can be damaged from travel, but also can be crushed under their own weight if not properly supported underneath. For that reason, the underside of the corm had a ‘dish’ of bubble wrap to support the bottom of the corm.

The corms were carefully unwrapped to check its condition after its journey from the US. The corm was in sound condition, moist and even showing bud development indicating that it is coming out of dormancy. The foul odor emitted by the corm was unmistakeable and very pervasive. At this point the corms were measured and then weighed. The corm currently in growth was 40.6 cm (16 inches) in diameter and weighed 22.6 kg (50 pounds). It is probably 25 years or older and was grown from seed collected in the USA.


Amorphophallus titanum, commonly known as Titan arum or Corpse flower, is a member of the Araceae family. As the latter common name suggests, when in bloom, the odour of this plant resembles the stench of rotting flesh or meat, to attract its pollinators, beetles and flies.

This herbaceous plant is native to the shady forests of Sumatra and has the largest unbranched inflorescence (group of flowers) in the world. The bloom is only for 48 hours before it collapses. The spathe, a colourful leaflike curved bract, opens on the first afternoon revealing the spadix, a spike of flowers. Overnight the female flowers bloom. On the second night the male flower blooms, producing masses of yellow pollen. After the second day the inflorescence closes completely. The flower may stay upright for another day before the spadix collapses. At its peak, the titan arum can reach up to 3 meters in height, and produces an underground corm (belowground storage organ) that can weigh up to 118 kg (260 lbs).

While in bloom, the Titan arum uses stored carbohydrates from the corm to heat the inflorescence to a temperature around 36°C, at least 9°C higher than it’s surroundings. It does this to disperse its potent aroma and attract its pollinators, carrion-eating beetles and flesh flies. When flowering is complete, the corm goes dormant until it is ready to produce its single huge photosynthetic leaf. It takes approximately 7 years of photosynthesizing and carbohydrate storage to replenish the resources that were used during flowering. The plant will not bloom again until the corm increases in size to around 16 kg (35 lbs) and there are enough stored resources to support the rapid growth of the inflorescence.

The Titan arum is listed as Vulnerable on the 1997 IUCN Red List of Threatened Plants. It can be found in many greenhouses around the world, but its flowering is rare in the wild and even rarer in cultivation. Since the first time it bloomed in cultivation in 1889, at the Royal Botanic Gardens at Kew in London, there have only been approximately 190 other occurrences of Titan arums blooming, with only 4 of those occurring in Canada.


Below are two graphs that show Phoebe’s height and the circumference of the bud from when she popped out of the ground till she bloomed.