Expert grower Derek Heathcote, whose seeds have received a seal of approval from the Queen, knows more than most about these beautiful blooms.
During the growing season, his family-run nursery, near Stowe-by-Chartley,Stafford, can have up to 4,000 plants flowering at any one time.
"I've grown sweet peas all my life. My dad grew them so when I was made redundant in 1992, I decided to start the business and it's snowballed since to what it is today," explains Derek.
Eagle Sweet Peas, which was awarded a royal warrant to supply seeds to the Queen in 2017, is constantly breeding new varieties and aims to release at least one each year.
For 2022, the new addition called Platinum Sensation has been created in honour of Her Majesty's 70 years of service.
"This has taken seven years to bring to fruition. It has four florets, on stout stems, with a very strong perfume. It starts off white and as it ages it gradually turns pale blue," explains Derek.
"The idea was that the Queen could have fresh-cut sweet peas for the Jubilee."
The nursery team, which includes his wife Jenny and son Andy, will sow their first batch of seed in late September, followed by further batches in January and March.
"We grow in succession to extend the flowering period from late April through to September," says Derek.
After the first batch of seeds germinate, they will be usually be planted in the ground in December. At Eagle Sweet Peas, they are cordon grown in cold greenhouses and polytunnels, which is said to result in flowers that are larger and of higher quality.
The strongest stem is selected and trained to grow up a cane or other support and tendrills and side shoots are continually removed. "This is a daily task. A sweet pea will grow up to five inches a day at this time of year. The plant can easily reach 20 to 30 feet," says Derek.
For sweet peas to flourish, Derek says they need rich soil and plenty of sunshine. "Like most plants, if you give them the right conditions and keep them well-watered, they will perform well. It's important not to over-water them. A lot of sweet peas are killed with kindness through over-watering and over mollycoddling."
According to Derek, gardeners should be looking to produce a plant with a long, straight stem with four well-placed florets. "You want a good colour and a strong perfume. All sweet peas have a perfume to a greater or lesser degree. Reds and oranges tend to have less fragrance and pinks, blues and whites always have the strongest perfume."
Over the years, Eagle Sweet Peas has exhibited at Chelsea Flower Show, where the business has won 10 gold medals, as well as at The Gardeners World Live Show, Hampton Court Palace Flower Show, Wem Sweet Pea Society Show, Tatton Park Flower Show, Shrewsbury Flower Show and Southport Flower Show.
Derek, who is also always happy to provide growing advice to those who need it, stocks nearly 50 varieties of sweet pea, many of which he has bred himself in Staffordshire.
The process starts with selecting two parent plants that have the qualities he is looking to combine in a new plant.
"If you've got a variety that produces a good colour and a variety that produces good seed, you can cross them so you have the best of both worlds.
"In the first year, the F1 stage, it will be the colour of one of its parents. You collect the seed and grow it on.
"In the second year, F2, there will be a myriad of colours, you pick the colour you want and then you will grow that on for a further year, which is F3. It should come true to colour and once you've got that, you can grow it on for another year - F4.
"We grow each new variety here for six or seven years to make sure that it is coming true to colour before the seed is sent to New Zealand.
"We have many varieties grown for us in New Zealand, which has a good climate for sweet peas, and the seed produced is sent back to us each April ready for the new season. It takes 12 months to grow enough seed to sell," explains Derek.
Once the seeds arrive from New Zealand, they are batch-tested three times to ensure they have an excellent germination rate before being packed ready for sale.
New varieties have been named after family members including Just Jenny for Derek's wife, Lisa Marie for his daughter, Katie Alice for his granddaughter, Henry Thomas for his grandson and Rebecca for his daughter-in-law.
Others include Geoff Hughes named for the late actor, known for his roles in Keeping Up Appearances, Heartbeat and Coronation Street, who was also a keen gardener.
"I've always got eight to 10 varieties on the go at any time. Some work out the way you want and others don't," Derek tells Weekend.
"I just love sweet peas. I enjoy the flowers - you can grow a sweet pea and it gives you a return."
See eaglesweetpeas.co.uk or call 01889 270215.