1st a disclaimer: I'm by no means a plant expert but these are my observations over the past years, in my attempts to grow Tulsi plants at home here in Toronto. If anyone wants to add to these tips, they are welcome to post in their replies

1. If possible, try to get as small a plant as possible, for your 1st plant, it has the highest chance of survival

2. Most plants you get in temples or Indian grocery shops, come in the styrofoam cups. 1st thing to do after coming home is to transfer the plant to a bigger pot with fresh potting soil

3. While transferring, do not pull out the plant as it may damage the delicate roots, instead cut through the styrofoam side and transfer the plant with the soil into the new pot, with minimal touching of the roots

4. Water them regularly, but neither flood them nor water them like you would cactuses, moderation is the key. I would say keep the water on the lower side than on higher side. as soon as you see the leaves drooping, give a little bit of water to dampen the soil

5. This is a common practice in Hindu homes, but do not ever plant incense sticks in the same pot as the plant while doing puja/arati of the plant. Today's incense sticks have harmful chemicals that can damage the plant

6. Once the plant grows vertically to a certain size, keep pruning it by cutting off the seeds that come out after some months. That way the plant remains small and remains alive. Appearance of seeds means the plant is reaching end of its life cycle, so cut them off and the plant should keep alive

7. These seeds and leaves can be used in puja & swallowed later (as is the practice in Hindu culture)

8. If you want to grow new plants (because eventually the original plant will die out after a year or two, or more if you are lucky), take the fully matured seeds, dry them up a bit and then put them in small styrofoam cups with soil, New plants should come out in a few days

9. Change soil of main pot, every 6 months

10. Do not keep in open in winter or fall. But they should always get enough sunshine from inside home

11. Do not keep near hot air vents

12. Do not keep in dark areas of the house or in the kitchen

13. Most of my plants in past years have died because I was away from home for a few days or weeks and there was no one to water them. They can probably survive a few days with flooded water, but that is risky. Have someone water the plants every day when you are away.

14. If you live alone or don't have anyone to look after the plant, use some innovative idea akin to "drip irrigation" to keep it going until you come back. For me, I have used a burette (that we used while we were students in Chemistry class) quite effectively, to keep them just alive for nearly a week

15. Lastly and most importantly, these are sacred plants and living breathing beings...plant and take care of them with love and respect and they will grow well for sure. Worship them every day and don't ever disrespect them by throwing eaten food or drunk left over water unto them. Tulsi is considered as mother in Hindu culture and treat it as such

Good Post.
15. Cutting the dried stems and leaves, using little plant food occasionally will help them to stay healthy.