There is one herb getting very popular in the supplement and herbal medicine world right now; St. John’s Wort.

This plant is a potent medicinal and is surprisingly easy to find, so I figure it is worth adding to our herb series that we have been working on.

Let’s check it out:

Scientific Name: Hypericum perforatum, plus several other species

Preferred Habitat: Meadows, forest edges, and clearings, especially near wet areas or bodies of water. Strangely it also likes gravel and rocky areas as well and doesn’t require very rich soil to grow.

Edible Parts:

Distribution: There are species of St. John’s Wort worldwide, and a handful in North America. This is a range map of all species on our continent to give you an idea of where it can grow:

Harvest Season: Early to mid summer, sometimes earlier or later depending on the species.

Key Identifiers: The flowers are small and yellow with 5 petals that have tiny black dots along the edges (I mean QUITE tiny!) the plant is usually around 1-3ft tall and the stem is slightly woody at the base. The oval-shaped leaves have tiny transparent dots in them which are visible when held up to the light, and some species have tiny black dots on the undersides of the leaves as well. The flowers also have many stamen (those little antennae in the middle of flowers) coming out from the center like whiskers.

Another easy way to tell is to crush a flower between your fingers (preferably a dry flower, not one that has dew or rain on it). If it makes a brownish-red stain then you’ve probably found it! That is the compound responsible for the medicinal effects.

Toxic Look-Alikes: Tansy (also called “tansy ragwort” or “St. James Wort”) is probably the most common look alike you’ll find that can look like St. John’s Wort from a distance. Closer up you’ll notice a lot of differences: the flowers while yellow, look more like tiny daisies and don’t have visible stamen poking out from the center, and the leaves look much more like dandelion leaves; toothed and lobed rather than smooth and oval-shaped.

Tansy ragwort has some medicinal use, but it should never be taken internally.

Medicinal Effects:

There is actually a lot of research done on St. John’s Wort.

Recent studies suggest that the herb can actually be far more potent than SSRIs with mild and moderate depression and with far fewer side effects.

The main benefits are:

These next benefits are still being studied:

This is another one of those herbs that is almost entirely medicinal and not necessarily something you cook with.

That said, it can be used for tea, infused oils, tinctures, salves, dried in capsules, ointments or balms.

Tea is one of the weaker ways to get the medicinal compounds but if you want to start with low dosage, that’s a good way to try it.

When taking this plant as a supplement it’s typically recommended that you cycle it. Try two to three weeks using the herb, then one week off. This will ensure that you’re maximizing the benefit without overdosing.

IMPORTANT: If you are on any medications such as antidepressants, birth control, blood thinners, immunosuppressants, or other drugs, please consult your medical advisor. This herb can be very incompatible and have some side effects when coupled with pharmaceuticals. Please do not mess with this.

Side effects include: photosensitivity (it can make you more likely to sunburn basically), gastrointestinal distress, serotonin syndrome, dizziness, fatigue, the usual base level poisoning symptoms.

It can also have negative effects on people with bipolar disorder, and may worsen some ADHD symptoms in certain people (although I don’t know how proven this is).

In addition, in some people it can occasionally make conception harder if you have hormonal imbalances or are taking other medication related to hormone function.

There are a number of St. John’s Wort species worldwide. Some in North America are non-native and naturalized, some are native.

In both cases they are pretty easy to grow and generally not picky.

They tend to prefer moderately fertile soil that is moist and well-drained like most garden plants, but actually tolerate poor soils fairly well.

In the Midwest here, St. John’s Wort can spread pretty aggressively so there is one main care item I recommend; in the spring, prune back the plants to roughly half of their height, and pull out any excess plants in the area you don’t want.

Other than that, if you want the plant in your garden and you don’t care if it spreads, then don’t worry about that last step!

Overall, I would still rank this as a low maintenance perennial herb.

See also: Easy perennial crops

The plant will also grow easily from seed, can propagate easily from cuttings, and is a good pollinator plant.

If you choose to grow it, I would recommend H. perforatum or another native species and not an Old World species unless you are extremely careful to keep it in check. In some areas these can either completely displace native species or become otherwise invasive so just be responsible!

I think this plant is worth having in the North American low effort landscape, but this is one plant that takes some knowledge and care to use properly. Don’t let that deter you, just let it teach you to be more intentional!

If you are interested in more edible or medicinal flowers, check out my old article on edible flowers.

There are a few cultivars of St. John’s Wort:

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