Photo: no rights reservedCC0 1.0via iNaturalist
Bitter bolete Plant Care
Caloboletus calopus
Updated · Sources · How we source care data
Caloboletus calopus, also known as the bitter bolete, is a mushroom species with a distinctive reddish-brown cap and yellow pores underneath. It is commonly found in hardwood forests in North America and Europe. It has lookalikes, and edibility must never be judged from an app.
Every 7–10 days
Bright indirect
50–70°F
60–80%
At a glance
How do you care for Bitter bolete?
Water Bitter bolete every 7–10 days, letting the top layer of soil dry out between waterings, and give it bright indirect light. It prefers temperatures of 50–70°F (10–21°C) and 60–80% humidity. Fertilize it every month during the growing season.
Where Is the Bitter bolete Native To?
- Albania
- Austria
- Belarus
- Belgium
- Bosnia and Herzegovina
- Bulgaria
- Canada
- Croatia
- Cyprus
- Czechia
- Denmark
- Estonia
- Finland
- France
- Germany
- Greece
- Hungary
- Iceland
- Ireland
- Italy
- Latvia
- Lithuania
- Luxembourg
- Malta
- Mexico
- Moldova
- Montenegro
- North Macedonia
- Norway
- Poland
- Portugal
- Romania
- Russia
- Serbia
- Slovakia
- Slovenia
- Spain
- Sweden
- Switzerland
- The Netherlands
- Ukraine
- United Kingdom
- United States
What Is the Bitter bolete?
Bitter bolete (Caloboletus calopus) belongs to the Boletaceae family within the Caloboletus genus. Bitter bolete is native to Europe,North America. Bitter bolete is also known as bitter cap.
Bitter bolete displays a mycorrhizal, terrestrial growth habit, reaching up to 1 ft tall with a spread of approximately 1 ft. Bitter bolete produces none.
Leaf size: approximately 6 inches.
How Often Should You Water a Bitter bolete?
Caloboletus calopus requires watering every 7–10 days. Allow the top layer of soil to dry between waterings to prevent root rot. Reduce watering frequency during winter when growth slows.
Watering Frequency
Every 7–10 days
Let soil partially dry between waterings
What Light Does the Bitter bolete Need?
Bitter bolete thrives in bright indirect light. Avoid placing Bitter bolete in direct, harsh sunlight for extended periods, as this can scorch the foliage.
Light Requirement
Bright indirect
What Temperature and Humidity Does the Bitter bolete Prefer?
Caloboletus calopus grows best at temperatures of 50–70°F. Bitter bolete prefers humidity levels of 60–80%. A pebble tray or humidifier helps maintain adequate moisture around the plant.
Temperature
50–70°F
Humidity
60–80%
What Soil Mix Works Best for a Bitter bolete?
Well-draining, rich organic mix. Good drainage is essential for Bitter bolete to prevent waterlogging, which leads to root rot and fungal issues.
How Often Should You Fertilize a Bitter bolete?
Feed Bitter bolete every month during the growing season (spring and summer) with a balanced fertilizer diluted to the strength on the label.
Pause feeding in autumn and winter, when growth slows, and never fertilize dry soil — water first.
Fertilizing
Every month
During the growing season
The PlantoScan app can remind you when to water and when to fertilize each plant.
How Do You Repot a Bitter bolete?
Every 2-3 years or when root-bound. Choose a pot one size larger than the current container, and ensure it has drainage holes to allow excess water to escape.
Is the Bitter bolete Toxic to Pets and Children?
Pet safety not verified
The ASPCA does not list Bitter bolete, so we can't confirm whether it is safe for cats and dogs. Keep pets from chewing it as a precaution.
This is a general caution, not veterinary or medical advice. If your pet ate a plant, contact your vet or animal poison control.
See all plants toxic to cats and plants toxic to dogs.
What Pests and Diseases Affect the Bitter bolete?
Bitter bolete is susceptible to slugs, snails, nematodes. Inspect the foliage regularly, especially along leaf undersides and stems. Treat infestations promptly with insecticidal soap or neem oil to prevent spread.
Yellow leaves, brown tips or drooping? See common plant problems and how to fix them.
Keep exploring plants
Bitter bolete is one of many species covered in the complete plant care and identification guide, which groups plants by genus, attribute, and popularity.
It belongs to the Caloboletus genus (family Boletaceae) — search all Caloboletus species in the plant lookup.
Bitter bolete thrives in bright light and direct sun — see other bright-light plants.
Related Plant Care Guides
Closely related plants with similar care requirements:
Sources
- Scientific name & taxonomy: Caloboletus calopus, family Boletaceae — World Flora Online.
- Pet toxicity: Pet safety not verified: the ASPCA does not list Bitter bolete, so we can't confirm whether it is safe for cats and dogs. Checked against the ASPCA plant list; any other toxicity note on this page comes from PlantoScan's plant database.
- Photo: Public domain, CC0 1.0, iNaturalist — original.
- Care values(watering, light, temperature, humidity, soil, fertilizing): PlantoScan's plant database, filtered by automatic plausibility checks — values that fail them are hidden. How we source and check plant data.
Spotted a mistake? Email info@upvision.media with the page link — we check and correct reported errors.
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