Successful Planting of Lupins

Which lupin variety to choose?

There are many varieties of lupins, which differ notably in their hues as well as their height, ranging from about 50 cm to 1 m. For small spaces, the ‘Minarette’ series offers compact plants of 30 to 60 cm, available in multiple colours. The Lupinus arboreus, more shrub-like, forms a beautiful spreading clump of 1.50 m topped with pale yellow spikes of intoxicatingly fragrant flowers.

Yellow-flowered lupins

‘The Chandelier’ and ‘Arboreus’ produce yellow flowers with a deep yellow banner.

White lupins

The ‘La Demoiselle’ Lupin produces tall, upright spikes of creamy white flowers with a peppery fragrance in June-July, perfect for adding height and a touch of light to borders and flower beds. ‘Gallery White‘ and ‘West Country Polar Princess‘ also produce magnificent white spikes that add luminous candles to any perennial or shrub border.

Pink or red-flowered lupins

‘The Châtelaine’ is recognisable by its pink flowers with a white banner. ‘My Castle’ and ‘Gallery Red’ produce beautiful red flowers.

Blue lupins

‘The Governor’ has blue flowers with a white banner. ‘Gallery Blue‘ and ‘West Country Persian Slipper‘ are superbly coloured with vibrant violet-blue flowers.

Lupin ‘My Castle’

Where to plant lupins?

This majestic perennial thrives in full sun or partial shade in borders and flower beds. Its elegant, upright habit makes it a superb structural plant, particularly well-suited to cottage gardens or country-style planting schemes. Lupins prefer cool, well-drained and slightly acidic soils. Avoid chalky soils where they quickly deteriorate. They combine beautifully with delphiniums, foxgloves or peonies to create stunning floral displays. For successful planting, allow 40 to 50 cm between each plant, as their taproots need space to develop properly.

When to plant lupin seedlings?

The Best Planting Seasons

The ideal periods for planting lupins are from March to May in spring, or from September to October in autumn. Spring planting allows the plants to establish strong roots before summer heat, while autumn planting encourages deep root development before winter. In mild climates, autumn planting is preferable as it results in earlier and more abundant flowering the following spring. In regions with harsh winters, opt for spring planting after the last frosts.

Young plants require close monitoring during the first few weeks after planting. Mulching around the base of the plants will protect their roots and maintain consistent moisture, essential for successful establishment.

Are Lupins Frost-Hardy?

Lupins are particularly hardy and can withstand temperatures as low as -15°C once well-established. This resilience varies depending on the plant’s growth stage. Young shoots tolerate temperatures of -10°C in well-drained soil but become more sensitive after reaching the 7-8 leaf stage, suffering damage at -5°C. To enhance their natural frost resistance, good drainage is essential. In regions with severe winters, a light mulch around the base is sufficient to protect the roots, without smothering the crown, which is sensitive to excess moisture.

How to plant lupins in pots?

• Prepare the planting hole carefully, twice as wide and deep as the root ball.
• At the bottom, place a layer of gravel or clay pebbles to ensure optimal drainage.
• Mix garden soil with coarse sand in a 2/3 – 1/3 ratio to lighten the substrate.
• Gently remove the plant from its container after moistening the root ball.
• Position it in the centre of the hole, ensuring the crown is level with the soil surface.
• Fill in with the prepared soil mixture, then lightly firm around the base. Planting too deep would weaken the plant and encourage crown rot.
• A good watering will complete the planting process.

What spacing between lupin plants?

For a harmonious display, maintain a spacing of 40 to 50 cm between each lupin plant. This distance allows the taproots to develop without competition and ensures good air circulation, reducing disease risks. In particularly rich soils, you can reduce the spacing to 35 cm for compact varieties. Planting too close together would encourage powdery mildew spread, while spacing them too far apart would reduce visual impact. For tree lupins like Lupinus arboreus which can reach 1.50 m, allow up to 80 cm between plants.

When and how to sow lupin seeds?

When to sow lupins?

Lupins are best sown during two distinct periods: in spring from April to mid-May, or in late summer from August to September.

How to sow?

• For optimal germination, soak your seeds in lukewarm water for 24 hours before sowing.
• In open ground, place 3 to 4 seeds per station, spaced 40 cm apart, at a depth of 1 cm in soil lightened with sand.
• Russell hybrid lupins require special attention when sowing under cover. Use deep pots filled with a mix of compost and sand, maintain a temperature of 18°C and constant humidity until germination.
• Keep only the most vigorous seedling per pot, as their strong taproot needs space to develop.

Your Lupin Calendar

• April-May: Plant your Lupins after the last frosts. Water regularly during the first few weeks after planting.
• June-July: This is the flowering period. Water your Lupins regularly during dry spells. Remove faded flowers to encourage the lupin to produce new blooms.
• August: Once flowering has finished, cut back the dried flower heads, unless you wish to collect seeds.
• February-March: This is the ideal time for sowing if you’ve collected seeds (to soften the seed coat, lightly rub the seeds with sandpaper just before sowing). Sow seeds in groups of three directly in position, keeping only the most vigorous seedlings.

How to make lupins flower again?

To encourage your Lupins to rebloom, regularly remove faded flowers. This will prompt the plant to produce more blooms. After flowering, cut the stems back to about 5cm from the ground, leaving the foliage. With adequate watering, they may flower again in autumn.

Lupins are perennial plants, meaning they can live for several years. However, they tend to become exhausted after a few years. To maintain abundant flowering, it’s recommended to divide the clumps every three or four years.