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.

Click here to view our full range of Magic Mushroom Spore Syringes 

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.