In Vastu Shastra, an ancient Indian architectural system, there is a belief that certain plants should be avoided within the living space as they may   

   bring negative energy or obstruct positive energy flow.   Here are some plants that some Vastu practitioners suggest avoiding indoors:

1. Thorny plants: Plants with thorns like cacti are believed to bring negative energy into the house.
2. Milkweed: This plant is thought to attract negativity and is considered inauspicious.
3. Bonsai trees: While bonsai trees are admired for their beauty and artistry, some Vastu practitioners advise against having them indoors as they may symbolize stunted growth or suppressed energy.
4. Dead or dried plants: Keeping dead or dried plants inside is believed to attract negative energy.
5. Cotton: Cotton plants are considered inauspicious according to Vastu Shastra for plants.
6. Bamboo plant inside: Bamboo is generally considered lucky in Feng Shui, but some Vastu practitioners believe that having it indoors may cause discord among family members.
7. Tamarind tree: According to Vastu, the tamarind tree may attract negativity and should be avoided near the house.  

Remember, while these beliefs are part of Vastu Shastra, they may not resonate with everyone. It’s essential to consider your own beliefs and cultural practices when incorporating plants into your living or working spaces.