Hello and thank you for contacting us.  

It looks like this might be St. John's Wort - maybe this is something you planted in past years?  Your photos appear to show translucent spots on the leaves which can be an identifying characteristic. However a better way to identify a plant is to look at its' flowers.  If you're willing to live with this plant for another month or so, St. John's Wort should bloom with the next few weeks. The flowers would be bright yellow with 5 petals.

This is the link to the Colorado Plant Database: https://coloradoplants.jeffco.us/PlantSearch?name=hypericum. It shows two varieties of St. John's Wort in Colorado. Click on each scientific name and you'll see additional identification information. To see photos, you'll need to do do an online search of each scientific name and likely find many images to compare to your plant.  The two varieties are:

• Southwestern St. John's Wort, which is a native plant and does not appear to be invasive. Generally native plants are better suited to Colorado, but if you are growing herbs for specific uses this might not be the preferred variety.
• Common St. John's Wort, with is on list C of the Colorado Noxious Weed Species list and can therefore be invasive. If you scroll down this page there is a good explanation of the A, B, and C list plants.  https://ag.colorado.gov/conservation/noxious-weeds/species-id#c.  For specific herbal uses, you'll want to determine which variety (or possibly both) will suit your needs.

Good luck with your herb garden - I'm guessing it's going nuts with this moist spring.  Let us know if you have further questions!

Jefferson County Master Gardener & Clinician Annette

Glad we could help you. Please be sure to contact Ask Extension again for any gardening problems you might have.

N.O.

Based on the photos, one other possibility is Purslane Speedwell (Veronica peregrina), in the Figwort family.  Here is a link to a fact sheet from NM State:  https://weeds.nmsu.edu/factsheet.php?weed_id=238.

For definitive identification, you can submit a sample to the Jeffco Plant Diagnostic Clinic (see below); $7 fee for Jeffco residents.

Best regards,

Mari