Why is it that I have a outdoor garden but my indoor plants dies  

That happens quite easily since most indoor plants are NOT looked after by nature, but must have their needs met by YOU!.. the right temepratures, lighting, sun/no sun, watering just right and making sure the water is there only as much as needed or more often, depending on the plant. While mother nature is looking after the outside and commending YOU for YOUR efforts too, the woeful ones are neglected indoors.
Very common this and the best solution is.. READ all you can about each plant you have and give it exactly what it needs. ..water, food, right temperature, right lighting, possible re-potting to a bigger pot, or new soil, dividing them in time and talking to them when you can.. they actually breathe in Carbon dioxide in the daylight and you breathe it out, so,, perfect, isn't it?You sound like a real gardener and this is often what happens. Just try a new approach to include the indoor kids too. You are going to be amazed and love the changes.. really!

Perhaps the plants you have are not suitable to grow indoor. In the past I also tried to plant something indoor but they all died. I think if you really want to have indoor plants. You still have to give them some sunshine now and then.

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