If you want to grow your own Malabar spinach from scratch, here are the steps.
1. Get some healthy stems of Malabar Spinach from your local Indian or Farmers' market. The stems don't need to be too long, but just make sure that they are not bruised or broken.
2. You can use the leaves for cooking, but save the stems in a glass full of water.
3. In about a week or so, you will notice that the stem now has roots. Let it grow some strong roots in water.
4. Now, plant the stem in a container or your veggie patch.
5. Very soon, the plant will grow and will have its own black seeds.
6. Sun dry those seeds and use them to plant next year!
7. Happy Gardening!
I use this same method (forcing the stems to root in the water and then plant them in soil) to grow my own mint and lemongrass.