Shamrock is one of those plants that’s only popular during the St. Patty’s Day for a large portion of the population.
The rest of the year? Not so much. It’s kind of like winterberry holly or mistletoe.
But didn’t you know that you can grow it in your house and enjoy it all year long (other than the summertime?).
This guy will even bloom for you. And produce a variety of leaves that you can enjoy even during winter.
Plus, it’s a super low maintenance houseplant that not a lot of people considering growing. So if you want something unique, this is it.
Let’s talk about how to grow and care for shamrock!
Last update: 2/16/23.
Guide Contents
Quick care guide: Shamrock (Oxalis spp.)
| Plant type | Perennial flowering |
| Origin | Ireland |
| Scientific name | Oxalis triangularis |
| Other names | Trifolium repens Clover Trefoil Dutch clover Summer plant Seamrog Oxalis Wood sprig |
| Soil type | Organic, rich, loose, loamy, sandy |
| Soil pH | 4.5-6.5 (acidic) |
| Sunlight requirement | Partial sun in warmer zones, full sun in cooler zones (8-11) |
| Bloom season | Fall to Spring |
| Colors | Green, lime, white, purple, pink, lavender, white |
| Max height | 12 inches |
| Max width | 8 inches |
| Low temperature tolerance | 50F |
| High temperature tolerance | 80F |
| Ideal temperature range | 60-70F |
| Humidity | Low to moderate humidity only (spray with water to raise humidity) |
| Watering requirements | Water when the top inch of soil is dry, more often for younger shamrock |
| Fertilizer requirements | Liquid, general purpose houseplant fertilizer biweekly during Fall to Spring |
| Plant food NPK | 10-10-10 |
| Days until germination | Usually not started by seed, but if so, takes up to 8 weeks to germinate. |
| Days until harvest | Non harvestable |
| Bloom time | Spring to Summer; foliage arrives 4 weeks after planting, flowers arrive 10 weeks after planting. |
| Speed of growth | Moderate |
| Hardiness zones | USDA hardiness zones 8-11 |
| Plant depth | From seeds: 1.0 inches From transplants: Same depth as original plant |
| Plant spacing | 2 inches between each Oxalis plant |
| Plant with | Japanese Painted Fern Amaryllis Other shamrocks |
| Don't plant with | Taller houseplants that block light or compete for nutrients |
| Propagation method | Transplants, plant division |
| Common pests | Thrips, whiteflies, vine weevils, blackflies, root bugs, mealybugs, spider mites, and worms |
| Common diseases | Ring spot, fungal rust, root rot |
| Indoor plant | Yes |
| Outdoor plant | Yes |
| Grown in container | Yes |
| Flowering plant | Yes |
| Beginner friendly | Yes |
| Care level | Minimal to none (easy) |
| Best uses | Indoor decoration, St. Patrick's Day, crafts, gifts. |
What’s Shamrock?
Oxalis spp., commonly known as shamrock, is natively from Africa and South America.
You may be accustomed to thinking it’s from kiss me Ireland, but it’s just a misconception. Shamrock is more than shamrock shakes or clovers in the field.
Now there ARE Ireland native varieties, but here in the US, we grow different Oxalis species.
You already know about it from decorating for St. Patty’s day. But they’re more than just a once-a-year plant.
These guys can be planted year-round for attractive, easy-to-care-for indoor pleasure. There are several varieties and they can be grown with just bright light.
This plant is a tiny house plant. Some species grow no more than 6-7 inches at most while others can topple 20 inches.
They can have a variety of delicate leaves that range in colors and shapes from lavender to white to green.
They also produce pretty blooms during the fall, winter, and spring. But not in the summer. They don’t like heat.
Shamrock will fold up their leaves at night and then open them again in the day when they sense light, so it’s one of those plants that “talk” to you.
Other names for shamrock include:
- Trifolium repens
- Clover
- Trefoil
- Dutch clover
- Summer plant
- Seamrog
- Oxalis
- Wood sprig
Where does shamrock come from?
The original Irish shamrock does come from Ireland. It’s a common lawn weed native to the country with its rhizomatous perennial leaves.
However, it’s been brought into other countries in different varieties.
In the US, you’ll commonly come across 3 different types that are differentiated mainly by their colors: purple, white, or green.
Appearance
Shamrock is more than just that tiny green plant you pick from the field. The houseplant can be anything from variegated to striped. The leaves can be purple, green, or pink.
Even the leaf shape can be different sizes with varying patterns. The blooms are white or pink with delicate petals that peek out from the clusters of leaves. The shamrock leaves are three sided and has a symmetric shape overall, but can vary depending on the plant.
Is shamrock poisonous?
Shamrock is indeed poisonous. Pets, people, and any other creatures should be kept away from Oxalis plants. Ingestion may cause acid poisoning or oxalic acid poisoning.
Types of shamrock
There are many different types of Oxalis species, each with its own variations in color, size, and more. In the US, you’ll find three that are most commonly grown.
Green Shamrock (O. regnellii)
Green shamrock is one with bright green foliage. They can be various shapes from triangular to spade-shaped.
This is the most popular cultivar here with its large white flowers that contrast perfectly with the lush green foliage.
There are other variations that include variegated leaves, such as Irish Mist, Hairy Woodsorrel, Wood Sorrel.
Purple Shamrock (O. triangularis)
False shamrock has those dark, purple-colored leaves with lavender/white flowers.
The blossoms are light in color while the foliage is dark, so it’s very striking to look at.
Some purple types include Love Plant or Mijke. The leaves are purple, pink, or lavender. They’re symmetric with three sides. They’re lighter in the center with a rosy color.
Why grow it?
That’s a good question. A lot of people grow this plant because it requires little maintenance, is drought tolerant, and can withstand desert temperatures down to 10F before it starts to wilt.
It can be purchased from the nursery and then replanted in the garden with ease when it’s still manageable. It also doesn’t need any work nearly all season other than occasional watering or pruning.
Plus, it looks awesome. This plant can attract beneficial pollinators to your yard, such as bees and hummingbirds.
Is it beginner friendly?
Yes, shamrock is very easy to grow and good for beginners. Once you get it set up and rooted, it takes care of itself.
You only need to water it and prune it. Plus give it some plant food once in a while. But that’s about it.
Can you eat shamrock root?
Shamrock root from SOME species is considered edible.
They’re large and have been cultivated as a crop in New Zealand, however, you should avoid eating the roots without consulting a professional.
If you don’t know how to identify the root properly, you can cause adverse effects from ingestion.
How to propagate shamrock
Shamrock actually can’t be harvested and then regrown from seed.
The plant can only be propagated by using existing shamrock tubers or buying a shamrock plant from the local garden center
This plant doesn’t produce viable seeds, so you won’t find them for sale. Either find a neighbor or friend that can give you some tubers or buy one from the nursery to get it going.
There are two main ways to propagate shamrock. Read them and see which one suits your style!
Propagating by transplanting
You can propagate by doing it the old-fashioned way. Buy a shamrock plant then grab a new pot to transplant it to.
You’ll want to use a planter that’s similar in size (diameter). Check the depth of the original shamrock roots. You’ll want to replant it into a similarly sized pot.
Fill the new pot ⅔ full with a well-draining, nutrient-dense potting mix. Don’t use garden soil. The pot should be well draining with multiple drain ports so it doesn’t get clogged. Shamrock can’t tolerate wet feet!
Gently uproot the original plant by tilting the container to its side. You can water it if the soil is tough or hard. If the roots are rootbound, use sterilized pruners to cut them from the pot.
This will loosen the shamrock plant so you can remove it from the original pot. Remove the soil from the shamrock roots. You won’t be able to get it all off, but you can get most of it off by using water to loosen it.
Replace the soil with a new potting mix. Don’t use the original soil because it’s likely depleted of nutrients. Be gentle when doing any sort of cutting. Trim only as much as you need to.
Recycling the soil may also introduce pests to your new pot. This is why you should remove as much as you can.
Place the shamrock into its new home. The plant should be placed about half an inch taller than the original container.
This allows it to sit in over time because it’ll seep into place. Fill around the shamrock with new soil. Pat it down. Then water it!
Keep the container within temperatures of 60-70F. It’s preferred to keep it cooler than warmer. Water it daily, but don’t overdo it. It should be moist but never wet.
Place the container next to a sunny spot, but not directly in the sun. use dappled filtered light only.
Propagating by dividing
You can also easily divide shamrock from a neighbor’s plant. You’ll need a virulent, established shamrock to extract plant sections from.
The ideal time to divide is in the fall, usually from October onwards.
This is because the plant will produce so you can extract! Autumn is when new shoots appear and are good for dividing the tubers in the plant. You can get more shamrocks to give away or expand your collection.
Get high-quality, nutrient-dense, well-draining soil. I know. Everyone says that. But it’s because it’s THAT important.
Next, grab a potter that’s well draining and has at least a 5” diameter. The material of the pot matters.
Choose one that’s terracotta or ceramic. Pretty much anything that’s porous. This material helps minimize temperature swings, which can be harmful to younger shamrock seedlings.
Don’t use plastic. It quickly heats up and doesn’t retain heat overnight. The pot should have at least 3 holes to drain. Double-check that it doesn’t require you to drill them yourself!
Fill the pot with potting soil one inch from the rim of the container. Let the soil sit by shaking it so it evens out.
Water it so it’ll settle down even more. You can give it a generous watering for the first time so it can build water pathways.
Gently tilt the pot so you can unearth the plant. You only need to take out the top few inches of soil to see the shamrock roots. Find a tuber that’s at least 1” in diameter with complete roots on it.
If it has stems, that’s preferred so you know you’re pulling a tuber that’s ready to root. The tuber can be removed by gently pulling it away from the others. But if it’s too tangled, ignore it.
Wipe off any debris or soil stuck on it. Then place it into the new pot at 1” deep. Cover it with a potting mix, but don’t pat it.
You want it near the surface of the soil line because if it’s too deep, it’ll likely rot or grow fungus. Plus, shamrock doesn’t like to be wet. Moist is the name of the game.
Put the pot in temperate conditions near a sunny window. The light should be bright, but filtered sunlight that’s NOT direct.
How to grow shamrock
You’ll find that shamrock is a beginner-friendly houseplant that requires very little work. Here are some suggestions to maximize your shamrock’s size.
Got questions? Post your questions in the comments.
Hardiness zone
Shamrock grows well in USDA hardiness zones 8-11. If you’re planning on growing it outside in your yard, be sure that you’re within these zones.
Temperatures that are too hot or cold will make it enter premature dormancy, which can limit those pretty blooms.
Otherwise, if you’re growing it inside your house, then you’ve got nothing to worry about. The zone doesn’t matter for indoor houseplants. So plant on!
Soil
Use well-draining, moisture-retaining soil with plenty of organic nutrients.
You can find a potting mix in nurseries that can be combined with plant supplements in order to get it saturated with nutrients. In other words, if you can’t find the soil you need for your shamrock, make your own!
Use organic soil if possible. Shamrock can be sensitive to harmful compounds in the soil column. Get loamy, sandy, well-draining acidic soil.
Soil pH
The soil pH should be on the acidic side, with a pH range of 4.5-6.5 for shamrock plants.
You can raise the pH of your soil naturally using soil amendments. Potting mix for indoor plants usually fulfills this requirement.
While the pH won’t make or break your shamrock’s production, it can help spruce up the colors and overall happiness of your plant.
Depth
The seeds should be planted 1” from the soil line and lightly covered. If transplanting, it should be planted at the same root depth as the original plant. If growing from cuttings, plant at least 5 inches deep.
Spacing
If you’re planting multiple shamrock tubers in the same pot, give them 3 inches between each to help encourage water evaporation and minimize competition for nutrients.
If you’re just planting one per pot, then space it at least 2 inches more than the longest root. It likes to be snug, but not too tight.
However, shamrock generally fares well when the root are confined so it can focus its energy on the production of blooms.
Temperature
Keep shamrock between 70-80 F during the daytime. During the night, it can tolerate temperatures as low as 50F.
This plant is both sensitive to temps that are too hot and too cold, so keep it in the ideal range. Dormancy is a common sign of temperatures that are way too hot for shamrock to tolerate.
If this is the case, move it away from the windows so it doesn’t face overheating. Premature dormancy is common for shamrocks that are kept directly in the sun.
Humidity
Shamrock prefers average, moderate humidity. Maintain levels between 40-50%. If the air is dry, you can use a humidifier or try placing it near wetter areas like the bathroom or kitchen.
You can also use a pebble tray with water or near a room humidifier.
Sunlight
For south facing windows, place them 2-3 feet away from the window on bright sunny days. It needs dappled light, never direct light. If it’s too sunny, it’ll get dehydrated and may even enter dormancy.
Full or partial sunlight is OK, but it depends on your location. Hotter zones should use filtered sunlight only.
Watering
Water shamrock when the top inch of soil feels dry. Don’t let shamrock dry out between watering sessions.
While it has some degree of drought tolerance, it’s not excellent by any means. Soil should remain slightly moist during all periods. Water 2-3 times per month. The soil should nearly dry out between watering, but not completely if you have a well-draining pot.
If the soil is draining poorly, switch containers or let it dry out between waterings as a temporary solution.
Plant food
Shamrock will benefit from nutrition in the soil but takes plant fertilizer as