Andrew West said a man dressed in a high-vis shirt and woman dressed like a landscaper knocked on the door of his Carosa Road home about 12.30pm on October 28.
Given the man’s intimidating stature, he said his wife did not answer the door.
The pair then lifted a large cycad plant, in a ceramic pot, from Mr West’s front porch and loaded it on the back of an unregistered trailer attached to a burgundy Ford Falcon sedan.
Mr West said the plant was worth about $900.
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READ NOWCCTV footage captured the incident, but the licence plate of the vehicle could not be verified.
Wanneroo police are investigating the incident.
Mr West described the man as aged 48 to 55 with a “very large and tall build” and sunburnt bald head. He described the woman as aged between 28 and 35 with blonde hair in a ponytail and skinny build.