Plant of the Week – Filius Blue Peppers

Filius Blue Peppers

Capsicum Annuum

Plant of the Week - Filius Blue Peppers

Recently, Penny posted some pictures of our garden and highlighted one of the peppers we are growing this year.  The Filius Blue Pepper caught a lot of peoples, attention and generated a lot of looks and likes on the posting.  I thought a bit more information about this fascinating little plant is in order.

Filius Blue Peppers produce a compact plant that rarely grows more than 24” tall and about as wide.  Such a low height makes Filius Blue a great choice for container gardeners who want not only a tasty pepper with a bit of bite but one that adds color of a different dimension to the garden. 

A Pepper of a different color

The peppers produced by the Filius Blue are, as you would imagine, blue.  Chili peppers come in a wide variety of colors but they are usually in the red or yellow spectrum.  This plant produces a dark blue small pepper from a plant and blooms that are almost as striking and the fruit.  It looks different than almost any other pepper plant.    Even the leaves will take on a bluish tint along the edges and tips.

Container Friendly

The peppers themselves can grow when mature to 2 ½” long and barely get 1” wide.  Many people grow the Filius Blue as an ornamental pepper. However, it is edible and, for an ornamental, surprisingly flavorful.  The secret is to pick at the right time for the amount of heat you want.  At the early stages of their growth, the peppers are small and deep blueish/purple.  At this stage, they can be thermo-nuclear hot so beware.  As the peppers mature, they will turn flame red, and the heat will moderate to a much lower level, and the sweetness of the peppers will become evident.

Hot or Not?

Speaking of heat, at their maximum, the Filius Blue peppers score about 50 to 60 thousand on the Scoville scale.  That puts it right in there with Cayenne, Aji, and Tabasco peppers.  Nowhere near the tongue blistering 1 million Scoville units of the Naga Jolokia pepper.

Transplant or Sow?

Like all peppers, Filius Blue peppers are hot weather loving plants.  They also need direct sun.  If you are preparing transplants, start your seed early in small cells or trays.  Sow the seeds in our recommended starting mix.  We typically start our peppers in the greenhouse in late December or Early January.  Once you are ready to transplant, follow our directions on transplanting seedlings.  Remember these are heat-loving plants so if you are trying to get an early start and are transplanting before that last magic frost date, be sure to cover them with cold frames or frost cloth — Harden off your seedlings for 2 to 3 weeks before they go outside permanently.

If you sow directly into the soil, make sure that the soil temperature is above 60 degrees before you sow your seeds.  Seeds should germinate in 3 to 7 days.  Be prepared to resow and fill in gaps.  Using row covers or cold frames to bring your soil temperature up is a good idea and can gain you as much as a week of earlier planting.

Feeding and Care

Once your plants are growing actively and have put on a few blooms, begin feeding them with compost tea (see our compost tea recipe) every few weeks through the growing season.  You can apply as a foliar spray or drench the bed.  You can do both without danger of overfeeding.

Whichever way you plan to use the Filius Blue pepper, as an ornamental, a garden pepper, or both, it makes an interesting addition to your landscape. 

For more information about garden and landscape plants, visit our website at and like our Facebook page at @westtexasorganicgardening