Nice lighting on the plant. The contrast of the wood ruler and the plant does not work for me. Having the word "constipation" so front and center is also a little awkward.
O.K. I'll admit - I got curious and looked up just what Tatsoi is ....now I'll have to look for it in the market for the taste sounds intriging. My best guess is that you are proud that you grew it yourself judging by including the ruler in the shot and/or it is a subtle reference to the 'size' of the flavor. Lighting is good on the plant itself with nice play of light and shadow on the leaves. As to the composition - it will not hold a vast majority of people's attention. It needs something more than the plain black background to 'flavor' it. The choice of ruler to measure the size of the plant is not very complementary - given that it 'advertises' Garfield Tea and what it is good for - constipation and headaches. A plain wooden ruler would perhaps been better.