I know, it's not St. Patrick's Day, so why am I writing about shamrocks? Because I want to, that's why. There's enough Irish in me that I get away with a lot.
I have been growing the same shamrock for over 13 years now. I bought it when we moved into our trailer, wayyyyy back in 2005. I have successfully kept it alive, and before I had the farm and learned to garden, that was quite a feat, let me tell you. I killed everything green in my house. Really. Who can kill a spider plant? This girl. Ivy? Buh-bye. If it's not an outside plant, it may as well already be dead. Except for this really lucky shamrock.
Along the way, I've learned how to take care of shamrocks, and now I have about 4 in my kitchen windowsill, 2 of which are starts from my 13 year old plant. I acquired an Iron Cross Shamrock back in March, and I don't think it's as lucky, because there are only 2 leaves left and it doesn't have any new growth. Not sure what I did wrong there. Oxalis isn't usually that fussy.
If you've ever wanted to grow shamrocks, I'll tell you, nothing is as pretty on a kitchen windowsill as they are. Most of them have tiny white bell-like flowers when they bloom, and they are so delicate they look like lace in between the green leaves. They don't get higher than about 8" tall, and they do well in smaller pots. I've divided mine every couple of years to make new plants and to encourage new growth.
Shamrocks don't need a lot of water. I only water them when they are completely dry, or when they start to sag. They usually let me know if they are thirsty. I also re-pot them every year and give them new soil. They like sandy soil with not too much compost, but just enough to keep the water in the pot for a few days. Also feeding them a good shot of nitrogen every few months will keep the leaves green and beautiful. Most of the time I just stir a teaspoon of used coffee grounds into the dirt, and they love that.
Shamrocks go through a period of dormancy, normally in the winter. The leaves will die back, and this is when they need a rest. Most websites tell you to move it to a darker location, but I have kept mine in the windowsill during dormancy and it works just fine. I cut all the dead leaves off, and in a week or so, the new ones pop up and it's as gorgeous as ever in about 2 weeks.
Sometimes in the summer I will put my potted shamrocks outside, but only if the weather is above 75 degrees. They don't like the cold, but keeping them outside makes the new leaves less 'leggy', and the plant grows bushier. I put them in a spot that doesn't get full sun, and they bloom all summer. If you pinch off the dead flowers and leaves, the plant will keep blooming. Just watch out for leprechauns in the pot, they dislike having their hair pulled.
If you need a little bit of luck, shamrock plants are a wonderful starter plant to keep. Trust me. My black thumb is proof!