These plants are a truly wonderful addition to your garden borders. Their towering blooms add interest, capture the eye, and are great for pollinators. Find out the answers to Google’s most-asked questions about Lupins, and maybe grow your own at home.
Where are Lupins native to?
There are several hundred species of Lupins to enjoy and grow at home.
Most of these are native to North and South America. However, there are a few varieties native to North Africa and parts of the Mediterranean too.
Are Lupins perennials?
Yes, Lupins are perennials, as they come up every year in the garden.
In terms of the plants lifespan, I’d expect them to last for approximately 6 years.
However, if you grow them from seed, they could last even longer!
Which garden style are Lupins best for?
Most professional garden designers would include Lupins in formal borders, gravel gardens, containers, and cottage gardens. Their flower shape adds interest and depth, particularly to garden borders.
Are they easy to grow?
Yes, Lupins are easy to grow. The secret is to grow them in the right spot.
Which brings me onto my next question…
Where do they grow best?
Lupins love to be in an open, sunny position. They like to be in a well-drained neutral to slightly acidic soil.
And you can grow them either in borders, or containers are good too.
If you are planting a container-grown Lupin, purchased from a garden centre, then plant them at the same depth that they were in the container.
Lupins grow better in borders than containers, as they suffer from lack of water, but with the right care they can look wonderful in pots.
I suggest planting them at the back of a bright, sunny border, with fresh compost.
Water them in well in the first year and stake them to hold them upright.
How do you grow Lupins from seed?
This is a great question. The first thing you need to do is choose your seeds. One of the first things you should consider is, am I trying to create a colour scheme?
Why does that matter? Well although great care has been taken when the seed packets are put together, you may find that as the seeds grow, the plants themselves are slightly different hues.
You may find that large seeds have a tough coating, so nick the shell with a knife and soak them in water for 24 hours before sowing.
Having done your seed prep, they need to be sown onto fresh compost in early to mid-spring.
And they should germinate within 10-14 days.
Growing Lupins from seed is more of a challenge – as they are prone to rot if they get too damp and they dislike root disturbance, which can make transplanting a little frustrating.
Your Lupins will self-seed when growing outside and they look like pea pod covered in fine hairs.
How big do they grow?
This depends on the type of lupin you have. There are two key types, Border Lupins, and Tree Lupins, and they grow to different heights.
Border Lupins – will grow typically up to 1.5 metres.
Tree Lupins – can grow up to 2 metres tall.
How long do they flower for?
You should see your first flush of flowers in late May through to June.
And if you are lucky, your Lupin can continue flowering until early August.
Are Lupins good for bees?
Yes, bees love Lupins.
Making them ideal for a pollinator-friendly garden.
And as a Beekeeper, I can confirm that my honeybees particularly enjoy Lupins.
Are Lupins frost hardy?
Typically, Lupins are hardy in UK if grown in free-draining soil in a sunny spot.
However, different types of Lupins have different tolerances to cold, so make sure you do your research before you buy.
If you have Lupins in containers, they are more susceptible to cold and frost, so protect them by moving the containers to a sheltered spot during late autumn and throughout the winter.
What colours do they come in?
Lupins come in a lovely array of colours from Whites, pinks, reds, yellows, blues, and purples.
Do they flower the first year?
Usually yes, though some varieties may not flower until their second year.
It may also depend on whether it was grown from seed or planted.
Do Lupins need a lot of water?
They require regular watering in their first summer to help the roots to establish.
However, it is worth being wary of them not liking to sit in damp, sodden soil.
Do Lupins change colour?
No, Lupins do not change colour. Though, you may think this happening when they start to self-seed.
When you start to grow seedlings, they will often revert to a more blue or purple colour, but this is not the same plant changing colour.
So your red lupin that looks paler, or more purple after a couple of years, is probably a new plant that has grown from self-seeding!
Will they flower twice?
If you prune your Lupins back immediately after flowering and feed, they will likely repeat flower within the summer period.
What do you plant with Lupins?
I’d recommend that you plant them with other ornamental grasses or other tall perennials such as delphiniums or bearded irises.
What do you do with Lupin pods after flowering?
Allow the pods to turn brown, then remove them from the plant and extract the seeds. You will know when they are ready, as they will start to crack open on their own.
If you don’t remove them from the Lupin plant, they will eventually self-seed.
When do Lupins die off (back)?
Lupins will typically die back in the winter as the frosts start to come in.
When do they start to grow back?
Your Lupins resprout in the Spring and will be flowering again by late May or early June.
Can you divide Lupins?
But this isn’t easy, and you may not always be successful. This is because they have a strong central tap root.
If you are going to attempt it, it needs to be done in spring. What you might find is your Lupin develops several crowns and these can be divided.
Though I find the best way to grow a new Lupin plant from an established one, is to take basal cuttings.
Will they spread?
Yes, if you allow them to self-seed. If you want to avoid this, I’d suggest that you harvest the seed pods before the seeds fall to the soil.
What are the common problems with Lupins, and how do I fix them?
Lupin anthracnose
- This is a fungal disease of leaves and the stems. It passes from plant to plant by rain-splashed spores.
- Causes brown areas of dead tissue may produce a mass of orange spores in wet conditions.
- Pick off and destroy affected leaves. Severely affected plants should be removed and disposed of.
- Avoid planting densely to prevent spread. Don’t save the seeds of affected plants.
Lupin aphid
- Sap-sucking true bugs. Some are known as greenfly or blackfly.
- These are large, greyish-white aphids, up to 4mm long. And they can be found in dense groups on the undersides of leaves.
- Heavily affected plants will wilt.
- You could spray aphid colonies with a diluted washing-up liquid solution. Combine a teaspoon of washing-up liquid with 3 litres of water. This stops the aphids from being able breathe.
- Encourage aphid predators, like ladybirds, hoverflies, and parasitoid wasps, into your garden.
Mildew
- Causes a white powdery coating on the leaves, shoot tips, and flowers.
- To control, prune the affected areas of the plant, and destroy them.
- Space out your plants so they are not too close together.
- Ladybirds are also prone to eating powdery mildew, so more reason to encourage them into your garden.
How do I stop slugs and snails from eating my Lupins?
Grow your lupins in containers – by raising them on pot feet, or putting the pot in a gravel tray, this naturally deters slugs and snails.
You could go out at night, pop on some gloves, and go slug hunting. Physically remove them from the garden during conditions that they like. For example, nights above 5°C, damp conditions/high humidity, are ideal.
There are some naturally slug-repellent barriers you could establish around your Lupins. These include used coffee grounds, eggshells, copper matting etc.
There is still debate about the effectiveness of these methods, but particularly for coffee grounds and eggshells, you aren’t buying anything new so could save you some money.
Grow garlic – close to the flowering perennials as the scent is proven to deter both slugs and snails.
Are Lupins poisonous to humans?
Many varieties are poisonous, and some are perfectly safe to eat, but you really need to make sure you know what variety you have.
The poisonous varieties contain a high concentration of a toxic alkaloid called ‘lupanine’. Symptoms of poisoning include dilated pupils, dizziness, and confusion.
Are Lupins edible?
Most varieties of Sweet Lupins are edible, though as I have already mentioned, there are some that are poisonous.
They have been grown for consumption since the ancient Egyptians, the Romans, and are often enjoyed now in South America and the Mediterranean.
Specific varieties that are often used for consumption are Lupinus albus (white lupin), and Lupinus angustifolias (narrow-leafed blue lupin).
Lupins should be soaked overnight, then boiled for an hour before using them in a recipe.
Do not eat them raw
They are used in stews, salads, burgers, or made into a ‘lupin hummus’. It has been ground into flour, which has been used as an alternative to soya.
Edible varieties are not very well suited to the UK climate. If you are unsure what variety you have, do not eat it.
Are Lupins poisonous to pets?
Lupins containing alkaloids poisonous to humans means it is likely that they are toxic to pets also.
Toxicity has predominantly been recorded in livestock, but the danger to domestic pets is also likely.
Dogs and cats are not known to find the taste of Lupins pleasant, and so are unlikely to eat it in large enough volumes to cause harm.
If you have a pet that likes to eat everything in sight, either avoid growing Lupins, or plant them somewhere less accessible to them in raised borders or containers that they can’t reach.
Lupins are a towering and colourful plant to include in your garden. If you have any questions about this or any other plant you want me to do a video on, please subscribe to my YouTube channel and leave a comment below one of my Google Questions videos.
David Domoney is a Chartered Horticulturalist, Broadcaster, and Author. David has worked with a number of the UK’s leading garden retailers as a plant buyer and strategic consultant. With more than 30 years experience, in horticulture, David is as passionate about plants now as he was when he bought his first plant at a village fete.
Leave A Comment