Companion planting is a popular gardening technique where different crops are grown side by side to help each other thrive. Some plants can improve growth, prevent pests, or enrich the soil for their neighbours, and it’s a simple method that’s been used in British gardens for generations.
One plant that continues to be a firm favourite is the sweet pea. Sweet pea is known for its colourful blooms and strong fragrance, and it’s often grown in flower beds, along fences, or up trellises. But it’s not just about looks. Sweet peas also help the garden by improving soil health through nitrogen fixation, a natural process where certain plants boost nutrient levels in the ground.
According to gardening experts at the Greg app, one of the best companion plants for sweet peas is spinach.
The two plants complement each other well and can grow together in harmony.
Sweet peas climb upwards, using little ground space, while spinach grows low to the ground with wide, leafy coverage.
This makes them ideal partners in a small garden, as they don’t compete for room. Instead, they make the most of the available space by growing at different levels.
The Greg app explains that sweet peas help improve the soil by fixing nitrogen during the growing process, which benefits nearby crops like spinach by enriching the soil.
In return, spinach’s broad leaves shade the ground and help keep the soil cool and moist – conditions that sweet peas prefer, especially during hot summer days.
Spinach is also quick to grow and can be harvested regularly. When planted alongside sweet peas, both crops can benefit from each other without getting in the way.
Gardeners using the Greg app are encouraged to pair these two plants for better results.
The app, which uses plant science to offer personalised growing tips, says sweet peas also do well near crops like carrots, turnips, and radishes.
However, it’s best to avoid planting them near onions or garlic, as these may hinder their growth.
Experts also recommend planting sweet peas in full sun with well-drained soil, and giving them support to climb.
Spinach prefers similar conditions but needs slightly more shade, which makes the pairing even more effective.