How to Grow Sweet Peas

Sweet Peas need at least 6 hours of sunshine a day, so choose a sunny position in an area with well-drained soil. Protection from strong winds is also recommended.

Improving the soil before sowing seed will give the plants a great start. Soil improvement is as simple as mixing two handfuls of Yates Dynamic Lifter Soil Improver & Plant Fertiliser into each square metre of soil.

Sweet Peas do best in slightly acidic to alkaline soil (pH 6.0 – 7.5). In acidic soils, the soil pH can be raised by applying Yates Lime & Dolomite Soil Improver Granules. 

Sweet Pea seeds are medium-sized and easy to sow. It's best to sow Sweet Pea seeds directly into the ground as transplanted seedlings tend to suffer transplant shock. For tall varieties, sow seed next to a 2 m tall trellis, tepee or support. Dampen the soil and sow seeds 15 - 25 mm deep and at the spacing indicated on the pack of your chosen variety. Don't water the soil again for another few days - if the soil is too wet the seeds may rot before germinating. Seedlings should start to emerge in 10-14 days.

In very cold areas, it's best to wait until spring to sow Sweet Pea seeds, as flowers can be damaged by harsh frost.

If the trellis or support does not reach the soil level, you may need to insert twigs or bamboo skewers into the soil, next to the seedlings. This gives them something to climb up until they reach the main support.

Keep the soil moist by watering at the base of the plants. To help reduce the incidence of diseases such as Powdery Mildew, avoid watering over the leaves. Applying a bark-based mulch, like Yates Dynamic Lifter 4 in 1 Mulch, around the base of the plants will help keep the soil moist.

Snails and Slugs are one of the biggest problems for young Sweet Pea seedlings, particularly during damp weather. Protect seedlings from Snails and Slugs with a light sprinkling of Yates Snail & Slug Bait.

Well-fed Sweet Pea plants will be healthier and produce more flowers, so regular feeding is important. Once the seedlings are established (around 4 weeks after sowing), start feeding the plants every 1 – 2 weeks with Yates Thrive Flower & Fruit Soluble Fertiliser. Mix 1-2 spoonfuls in a 9 litre watering can and apply around the base of the plants.

Sweet Peas are legumes so they will produce some of their own nitrogen - the nutrient that promotes green leaf and stem growth. However, Sweet Pea plants require other nutrients including potassium, which promotes flowering. Yates Thrive Flower & Fruit Soluble Fertiliser is rich in flower-promoting potassium.

Depending on the variety, Sweet Peas will start flowering 12-16 weeks after sowing. Once they start flowering, pick bunches of flowers as often as you like. Frequent picking will help promote a longer flowering season.

Yes, all Sweet Peas can be grown in pots and containers. Tall climbing varieties need a tepee, trellis, or other support to grow up. While compact varieties, such as Yates Sweet Pea Bijou Semi Dwarf, require no support and are ideal for pots and hanging baskets.

Choose a pot or trough at least 40-50cm wide and 20 cm deep. Position in full sun in a wind-protected spot.

Fill the pot with quality potting mix, such as Yates Premium Potting Mix with Dynamic Lifter and water well to moisten the mix.

For climbing Sweet Peas, place the pot next to a wire trellis attached to a wall or fence. Or insert a wire pyramid or tepee firmly into the potting mix.

Sow Sweet Pea seeds at the recommended depth and spacing on the pack. For climbing Sweet Peas, sow seeds at the base of the support. Don't water the potting mix again for another few days, as if the mix is too wet, the seeds may rot before germinating. Seedlings should start to emerge in 10 - 14 days.

If the trellis or support does not reach the soil level, you may need to insert twigs or bamboo skewers into the soil, next to the seedlings. This gives them something to climb up until they reach the main support.

Keep the soil moist by watering at the base of the plants. To help reduce the incidence of diseases such as Powdery Mildew, avoid watering over the leaves. Applying a bark-based mulch, like Yates Dynamic Lifter 4 in 1 Mulch, around the base of the plants will help keep the potting mix moist.

Snails and Slugs are one of the biggest problems for young Sweet Pea seedlings, particularly during damp weather. Protect seedlings from Snails and Slugs with a light sprinkling of Yates Snail & Slug Bait.

Well-fed Sweet Pea plants will be healthier and produce more flowers, so regular feeding is important. Once the seedlings are established (around 4 weeks after sowing), start feeding the plants every 1 – 2 weeks with Yates Thrive Flower & Fruit Soluble Fertiliser. Mix 1-2 spoonfuls in a 9 litre watering can and apply around the base of the plants.

Sweet Peas are legumes so they will produce some of their own nitrogen - the nutrient that promotes green leaf and stem growth. However, Sweet Pea plants require other nutrients including potassium, which promotes flowering. Yates Thrive Flower & Fruit Soluble Fertiliser is rich in flower-promoting potassium.

Depending on the variety, Sweet Peas will start flowering 12-16 weeks after sowing. Once they start flowering, pick bunches of flowers as often as you like. Frequent picking will help promote a longer flowering season.

You can grow Sweet Peas on a teepee using a pyramid of bamboo poles or tomato stakes. Use 5-10 poles/stakes that are 1.5 m or longer. Tie them together with twine, securing them 10-15 cm away from the tip. Push the other end of each pole/stake into the soil in the shape of a circle. Push the pole/stake far enough into the soil so they're stable, secure and even. Lastly, wind the twine down and around the teepee to give the Sweet Pea plants extra places to climb, and to help strengthen the teepee.

In warm climates, such as Brisbane, the best time to sow Sweet Peas is in May.

In temperate climates, such as Melbourne, Sydney and the southern tip of Western Australia, the best time to sow Sweet Pea seeds is in April and May.

In cool climates, such as Tasmania and the Australian Capital Territory, the best time to sow Sweet Peas is in March, April and May. In very cold areas, it's best to wait until spring to sow Sweet Pea seeds, as flowers can be damaged by harsh frost.

To promote healthy plants and lots of flowers, feed Sweet Peas with a high potassium liquid fertiliser. We recommend applying Yates Thrive Flower & Fruit Soluble Fertiliser every 1 – 2 weeks. Mix 1-2 spoonfuls in a 9 litre watering can and apply around the base of the plants.

Sweet Peas that are sown in autumn will flower in spring. In cool and temperate areas, Sweet Peas that are sown in early spring will flower in early summer.

Once Sweet Peas are established they can be tolerant of light frosts. To reduce frost damage you can spray plants with Yates Waterwise DroughtShield. As well as watering plants, including the foliage, very early in the morning after a frost. In very cold areas, it's best to wait until spring to sow Sweet Pea seeds, as flowers can be damaged by harsh frost.

At the end of the season, trim the Sweet Pea plants off at the base leaving the roots in the soil, and cut up all the leaves and stems into small pieces to use as mulch. This can add valuable nitrogen and organic matter back into the soil. Any flowers you grow after Sweet Peas will appreciate the additional nitrogen that the plants leave behind. Flower seeds to sow in Spring after Sweet Peas include Sunflowers, Cosmos, and Marigolds.

Sweet Peas can be poisonous to humans and animals if consumed in large quantities. As Sweet Peas are poisonous, it's best not to plant them near edible plants.

The level of fragrance in Sweet Peas can vary. Some of the most fragrant Sweet Peas include Yates Sweet Pea 'Original' and Yates Heirloom Sweet Pea Old Fashioned.

Sweet Peas with long stems are ideal for cut flowers. Sweet Pea varieties with the longest stems include Yates Sweet Pea Colourcade and Yates Sweet Pea Bijou Semi Dwarf.

One of the world's leading breeders of Sweet Peas, Dr. Keith Hammett, shared a pearl of wisdom with us about growing Sweet Peas for cut flowers. From many years of experience, he has learnt that the difference between day and night temperature dictates the stem length, with a 20 °C difference being ideal. For example, 25 °C during the day and 5 °C at night will encourage longer stems.

Tall growing Sweet Peas that are perfect for growing on a fence or trellis include Yates Sweet Pea Original, Yates Sweet Pea Blue Reflections, Yates Sweet Pea Colourcade and Yates Sweet Pea Old Fashioned.

Depending on the variety, Sweet Pea plants will start to flower from around 12 weeks after sowing. If the plants look healthy, you can help promote flowering by regularly applying a high-potassium fertiliser like Yates Thrive Flower & Fruit Soluble Fertiliser.

Yellowing leaves can be an early sign of the disease Powdery Mildew. Powdery Mildew also appears as white talcum powder-like spots over leaves.

To help reduce the incidence of powdery mildew grow Sweet Peas in an airy and sunny location, and only water plants at their base to help minimise wet leaves. At the first sign of Powdery Mildew, spray plants with Yates Rose Gun.

Sweet Pea plants can be prone to Downy Mildew. Early symptoms of this disease include stunted or distorted growth of developing seedlings. The leaves of older plants may turn yellow and develop greyish tufty spores on their undersides. Downy mildew is more prevalent during periods of high humidity.

To help reduce the incidence of Downy Mildew, grow Sweet Peas in an airy and sunny location, and only water plants at their base to help minimise wet leaves.

Sweet Peas can be prone to a few common pests, including Aphids, Thrips and Mites. All of which can be treated using Yates Rose Gun.

Aphids are tiny green, brown, yellow or black sap-sucking insects that cluster on leaves and stems. They can damage the leaves and plant health will suffer. As soon as Aphids are noticed, spray the plants with Yates Rose Gun.

Thrips are tiny slender insects, only 1-2 mm long, and can be different colours ranging from yellowish to black. They're sap-sucking pests and cause Pea leaves or pods to develop silvery or mottled patches. You may also notice small dark droppings. As soon as Thrips or their damage are noticed, spray plants every 14 days with Yates Rose Gun ensuring all sides of the foliage are covered.

Mites are very tiny sap-sucking pests that can attack either the foliage or pods of Peas. Symptoms of Mite infestations include yellowing leaves, stunted plants or new leaves being twisted. Control Mites on foliage with regular sprays of Yates Rose Gun.