If you’re exploring mushroom spores for microscopy, B+ is one of the most well-known and widely studied strains available in the UK.

Known for its clear visibility under magnification and consistent spore structure, B+ is often recommended for beginners and experienced hobbyists alike.

In this guide, we’ll break down what makes B+ spores unique, what you can expect under the microscope, and how they compare to other popular strains.

What Are B+ Mushroom Spores?

B+ is a strain of Psilocybe cubensis known for producing dark, clearly defined spores that are easy to observe under magnification.

Like all spores sold in the UK, B+ spores are used for:

• Microscopy
• Taxonomy studies
• Educational research

Under a microscope, B+ spores typically appear:

• Smooth and oval-shaped
• Dark purple-brown in colour
• Consistent in size and structure

👉 If you’re new to microscopy, you may also want to read:
What Are Mushroom Spores

Why B+ Is Popular for Microscopy

B+ has built a strong reputation due to its clarity and reliability when viewed under magnification.

Key reasons it’s popular:

• Easy to observe spore structure
• Clear contrast on slides
• Widely available in the UK
• Suitable for beginners learning microscopy

Compared to some other strains, B+ spores are often described as visually clean and easy to analyse, making them ideal for learning.

B+ Spore Prints vs Spore Syringes

B+ spores are commonly available in two formats:

Spore Prints

• Ideal for studying natural spore patterns
• Show distribution and density clearly
• Preferred for detailed visual analysis

Spore Syringes

• Spores suspended in sterile solution
• Easy to apply directly to slides
• More convenient for beginners

👉 Not sure which to choose?
Read our full guide:
Spore Syringes vs Spore Prints – UK Guide

Is B+ Legal in the UK?

In the UK, mushroom spores themselves are legal, as they do not contain active compounds.

However, they are sold strictly for:

• Microscopy
• Research
• Educational purposes

They are not intended for cultivation or consumption.

Where to Buy B+ Spores in the UK

When choosing a supplier, it’s important to look for:

• Clear microscopy-only disclaimer
• Consistent sterile preparation
• Accurate strain labelling
• Real product images
• Discreet UK shipping

👉 For a full breakdown, see:
Where to Buy Magic Mushroom Spores UK (2026 Guide)

Final Thoughts

B+ remains one of the most popular strains for microscopy in the UK — and for good reason.

Its clear structure, ease of observation, and consistent appearance make it a strong choice for anyone looking to study mushroom spores under the microscope.

If you’re building your understanding of different strains, B+ is a reliable place to start.