Sweet pea Spencer Allan Williams

This popular climbing annual boasts flowers in delicate shades of lavender, lilac, and light purple. The flowers grow on shorter stems, making them a perfect choice for smaller floral arrangements. Throughout the summer, the plant produces a flood of these beautiful flowers.

It will thrive best in full sun or partial shade. Choose a spot that is protected from strong winds, which could break the delicate shoots. The soil should be well-drained and warm. Plant the seedlings 10 to 20 cm apart to give them enough space and air to grow.

This climbing annual grows very vigorously and reaches an impressive height of 100 to 250 cm. Sturdy support is an absolute necessity for it. Install a taut garden netting, wooden trellis, or long poles arranged in a teepee shape, for example, right when planting the seedlings. The plant will actively climb the support on its own using its small tendrils.

Yes, growing them on a terrace or balcony is possible, but it requires some special care. Given that the plant can reach a height of up to 2.5 meters, you will need a sufficiently large and deep planting container (at least 30–40 cm in depth and width).

The soil in the pot must be nutrient-rich and well-draining. You must firmly secure a sufficiently tall trellis or support poles in the container. Also, keep in mind that the substrate in a pot will dry out much faster in the summer, so it will require more frequent moisture checks and watering.

Pinching is a very useful step for sweet peas to obtain a strong, bushy, and richly flowering plant. Once your pre-grown seedlings grow a bit and form a small, sturdy plant (usually with 3 to 4 pairs of true leaves), simply cut or pinch off the top. This stops vertical growth, forcing the plant to produce side shoots and branch out beautifully.

The sweet pea needs regular, medium-intensity watering. The soil should always be slightly moist and should never dry out completely. However, avoid long-term waterlogging, which often leads to root rot.

We recommend watering the plant slowly and directly at the roots. Watering with a hose over the leaves is not suitable, as it increases the risk of fungal diseases.

The usual flowering period for this variety begins in May and continues through June and July. The secret to having blooms until the beginning of August is the regular removal (pinching off) of faded flowers.

If you allow the plant to produce green seed pods, it will redirect all its energy into seed production and will quickly stop blooming. However, if you continuously trim off all wilted flowers, the plant will be forced to keep producing new buds.

For sowing, it is best to choose a 9x9 cm pot because the sweet pea has a longer root system and needs space. Place 2 to 3 seeds in one pot. It is absolutely crucial to cover the seeds with a layer of substrate, as they require complete darkness for proper germination.

Keep the substrate consistently moist, but not waterlogged. The ideal temperature for germination is 16 to 20 °C. If you follow these conditions, the first green sprouts will appear above the surface in 7 to 14 days.

You can start sowing in two main waves:

• Autumn sowing (November and December) – ideal for obtaining strong seedlings and very early flowering in the coming season.
• Winter sowing (January–February) – a classic choice for standard cultivation.

Pre-growing takes an average of 6 to 8 weeks.

The most common reason is root damage during transplanting. Sweet peas have relatively deep roots and tolerate disturbance to the root ball very poorly. Therefore, you should always start them in individual pots (e.g., 9x9 cm in size) and plant them outdoors with the entire compact root ball of damp substrate intact, without disturbing it.

Another cause could be premature planting into cold soil or an unexpected return of severe spring frosts.

Caution, it is not. All parts of the sweet pea are poisonous and inedible. It contains toxins that can cause health problems if ingested. The ripe seeds and pods, which resemble edible peas, are particularly tempting but dangerous.

Definitely yes! That is also where its Czech and Latin name (Sweet pea - Lathyrus odoratus) comes from. The 'Spencer Allan Williams' variety is characterized by a very intense and sweet fragrance, which can scent an entire terrace, garden, or room if you bring the flowers inside in a vase.

Yes, Sweet pea is an excellent annual for cutting. Although the variety from the Spencer Allan Williams series has slightly shorter stems than some other cultivars, it is perfect for smaller, romantic spring and summer bouquets. Ideally, cut the flowers early in the morning when the whole plant is fresh and hydrated, and choose stems where the flowers are half-opened. They will last a long time in a vase with clean water and beautifully scent your home.

In terms of insects, the biggest enemy of sweet peas are aphids, which love to feed on the tender young tops of the plants. If they appear, treat them with a soap solution or an appropriate insecticide spray.

As for fungal diseases, sweet peas are often troubled by powdery mildew (manifesting as a white coating on the leaves), especially towards the end of summer. As a preventative measure, it is helpful to maintain the recommended plant spacing (for sufficient air circulation) and to water carefully, applying water directly to the roots rather than over the leaves.