Sweet peas are a much-loved favourite among many gardeners, admired for their beautiful blooms and heavenly fragrance. Whether you’re growing them in pots, along fences, or over an archway, sweet peas are the ultimate cut flower that bloom from late Spring to mid-summer when properly cared for.

Find out all about these amazing flowers, including when to sow sweet peas, in our ultimate guide below.
1. Choosing Sweet Pea Varieties

There are over 160 species of the Sweet pea genus, Lathyrus worldwide. The most popular of these for home gardeners is the annual species, Lathyrus odoratus.
Annual Sweet Peas

As annuals, these sweet peas are grown from seeds each year, providing the perfect opportunity to experiment with different varieties. When selecting which sweet pea varieties to grow, you can consider three main factors: flower size, colour, and fragrance.

‘Spencer’ or ‘old-fashioned’ mixed varieties are popular choices, known for their wide range of colours and strong scent. You can also find an abundance of modern varieties that are two-toned, streaked, or extra frilly, adding even more visual interest.
Perennial Sweet Peas

For those who prefer a perennial plant, Lathyrus latifolius offers an option that returns year after year—though, unfortunately, it lacks the strong signature fragrance of annual sweet peas

2. Sowing Sweet Peas
When to plant Sweet Peas

The best time for sowing sweet peas is in the cooler months. They can either be Autumn or Spring sown in the period from October to March. Autumn sowing sweet pea seeds gives them a head start and allows you to enjoy early blooms by late spring or early summer.

Sweet peas have deep-growing roots, so it’s important to choose a container that accommodates this. Deep pots, root trainers, or even a biodegradable option of toilet roll tubes work well.
How to Sow Sweet Peas

Step 1 – Fill containers with homemade or quality peat-free compost
Step 2 – Sow two seeds per tube or pot at a depth of 1.5 cm
Step 3 – The seeds should germinate in about 2-3 weeks, depending on the temperature.