Grow incredible sweet peas
Growing sweet peas successfully is not rocket science. Here are our top tips:
Use fresh seed for better germination rates. Sow seed a knuckle deep in trays or pots and keep out of the way of the marauding mouse who loves to eat a germinating sweet pea seed more than anything.
Successionally sow two or three crops of sweet peas, and sow fewer than you think you'll need. It's better to keep cutting ALL the flowers on ten or fifteen plants, than being overwhelmed by the flowers on thirty or fourty plants and finding your sweet peas go over quickly. I would sow your first crop in autumn, say, first October, and your second, outside in March.
Sow sweet pea seed in deep pots or root trainers - this way they have space to get their roots down which they like to do.
Pinch out the sweet pea seedlings by cutting off the shooting stem so that you leave only two sets of true leaves. This will encourage the plant to branch out, so giving you lots more flowers.
Plant sweet peas out, protected from frost, from mid-March onwards, into very houmus-rich soil - sweet peas like full sun but they don't like their roots to dry out, so give them good, water-retaining compost to grow out of.
Cut ALL the sweet pea flowers as they flower, and if you see seed pods developing then cut those too (unless you want to save seed for next year.)
Water sweet pea plants in dry weather and they'll thank you with long stems and fantastic flowers.
For the most scent grow the heritage varieties like Matucana and Cupani and Pink Lady, but for really big, showy flower heads, and still plenty of amazing scent, grow the Spencer varieties which give you masses of flowery bang for your buck.
If you have two lots of sweet pea seeds sown, one in the autumn, and one in spring, you can let your first crop go over when it's had enough, and have a whole nother crop to enjoy.
If your sweet pea plants develop mildew you're over-watering, or go yellow, they're hungry. We recommend sea-weed solution, very weak, for feeding sweet peas when they're flowering, perhaps once a fortnight.