Lupins provide a stunning flowering display which is what makes them so popular with gardeners up and down the USA. But what do you do with lupins once they have finished flowering and the slower spikes are starting to die off? Let’s have a look below.
What to do with lupins after flowering?
You have two main choices for what to do with your Lupin flower spikes after they have finished with their wonderful summer display.
Deadhead
The first option is to deadhead the flower spike. This will encourage new flower growth giving you another beautiful floral display and extending the flowering season of the lupin.
Let It Seed
Or, you could let the flower go to seed. You can then grow new lupins from the seed pods or let the lupin self seed in place.
Getting your lupin ready for winter
After dealing with the flower spikes you need to start getting your lupin ready for winter. as the autumn nights start drawing in it will be time to think about cutting your lupin back. To help your Lupin survive the cold winter nights it is highly advisable to cut it right back to base in late Autumn.
While this may seem harsh the plant will be just fine as all its energy will be stored up in the roots. The plant will then be ready to explode back into life come spring, bringing you better than ever growth and flowering.
Overwintering your lupins
The vast majority of Lupins will be just fine left outdoors over winter but this can obviously change depending on what zone you are in.
If you have really cold winters and prolonged periods of freezing temperatures then will you have to bring your lupins inside into a greenhouse or another sheltered spot.
It is worth noting however that pot-grown lupin will be more vulnerable to frost, as all pot-grown plants are, so moving them into a greenhouse or another sheltered spot is advisable.
The heart of your lupin plant is deep down in the roots so they survive cold spells just fine when left in the ground. When in a pot, however, the heart of the plant is beneath much less soil, particularly from the sides, and as such can end up getting frozen.
Did you also know that lupins can self-seed into your soil! So keep an eye out for any little seedlings the following spring growing around your lupins.
Cutting Back Lupins For Winter
Lupins should be cut all the way to the ground at the end of autumn. This may sound drastic but it is part of the natural lifecycle of a lupin plant so be brave!
You can cut everything off right down to the ground so there is just a stump left of where your plant once grew. This will happen naturally anyway and by doing it ourselves we help to keep the rootstock of the plant healthy.
All of the energy of a lupin is stored in its roots underground overwinter then come the right spring the plant will roar back into life and provide you with yet more wonderful flower displays.
Do Lupins Come Back Every Year?
Yes, your lupins will come back each spring year after year. They do have a lifespan though of around 6 years. This can be shorter or longer but this is a good average.
One thing you will notice as the plants start to age is that the blooms get smaller and smaller.
Because of this many gardeners replace their lupins with a younger plant after 3-4 years. One great way to get new plants is to split the roots of an older plant.
How to split lupins
Here is my quick guide on how to easily split your lupins in order to get brand new plants that are guaranteed to be the same color as the parent!
Give Them A Good Soak
Before digging your lupins give them a good soak, a nice rainy day is actually the perfect time to split a lupin as the rain will keep everything nice and wet for you.
Dig The Lupin Up
Dig a large area around the base of the lupin and gently pull it up, aiming to keep as much of the root structure intact as possible.
Wash Off The Soil
Then wash all of the soil off the roots so you can get a really good look at it.
Cut With Sharp Knife
Use a sharp knife to cut away a section of the plant from the outside edge.
Aim for something around 2 inches in diameter and choose a section that looks nice and healthy.
Plant Cutting In Small Pot
Plant this cutting into a small pot full of multi-purpose compost. You will want to give it plenty of watering and then move into a sheltered spot with plenty of light.
Move Indoors Or Into A Greenhouse
A greenhouse is perfect but if you don’t have one a sunny windowsill will work just fine.
Plant Out Once There Is Lots Of New Growth
Grow the lupin on in this spot until it has plenty of new growth on it, once it has healthy growth you can think about moving it back into the garden.