Preparing ground on field of lupins for growing

Hey all!

Recently bought a small house with some land. (In Sweden) This year we only made a small patch for herbs but for next year we want to grow lots more.
There is a really nice area with sun all day and the soil seems to be very good. Problem is it's just full of lupins. Partly I guess that's good because they bind nitrogen to the ground and their deep roots kind of tills the soil.
But they have completely taken over!

It seems like the perfect spot for growing though. Do you think sheet mulching would work for this? Or are they so tough they get through the layers? Anyone had some experience with this or got some ideas?
We got the advice from a local to hire someone to get a tractor there and dig up the roots but we dont want to do that and ruin the soil structure.

And yes we want to keep some of them for bees insects etc


Regards
Henrik

Henrik, I too have ideal growing conditions for lupins. I wish I could get the pink ones to do what yours have, but mine are mostly blue. Anyway, I don't try to remove them, but I have managed to kill them, accidentally. It seems they use a lot of their energy to come up in the spring and if you just mow them down once or twice if they try to come back, that seems to be enough. I don't know if it's already too late in the season for this to work this year. They should have the earth prepared nicely all by themselves.

OMG that is absolutely beautiful..sure I would think that sheet mulch should work well, as Lupins can be quite iffy if they are hindered in their growing cycle..but what great luck in getting something so full of all the great nitrogen !! I sure wish I had those..and wish you were able to send seeds..(probably couldn't overseas !!)..

please let us know how things work out.

I think if you are going in the direction of a food forest, I would leave the lupins in that area and dig the hole and put in the baby tree, and maybe toss in some large leafed DA's that will be good chop and drops, like comfrey or rhubarb or swiss chard..etc..and then lay down the large leaves over the emerging lupin babies..in the spring..to smother them..round the trees..

IF you need to open up a spot that has no lupins at all, say for annual vegetables..etc..lay something down on the lupines to kill them off..should work fairly quickly with my experience with the lupines here..but maybe yours are more vigorous??

Here in Iceland, the invasive lupins are both hated and loved.

Loved because they are so beautiful in a country generally devoid of showy flowers.

But hated because the lupins are so agressive and they quickly form huge widespread monocrops of only kupins, smashing all other plants into shade. They are quickly covering our vulcanic wastelands and deserts. Where there was a desert 15 years ago, now you can drive for 100km non-stop with lupins. It's a gorgeous sight, but obviously a monocrop.

In my garden, I used them to cut and mulch (a lot), their mulch is quite good. But if you have a terrain with lupins, first you must eliminate all of their roots (a small piece, even if standing in top of a rock, will generate a new plant quickly and send its roots deeply. So, you will have to till that soil. unless you grow stuff higher than 1 meter high.

Second, you must eliminate all seeldings. Thankfully the lupin needs 1 year to establish itself, so in the first months its easy to remove the seedlings. But the adult plants have very thick and agressive roots (but in Iceland, some horsetails and the invasive coltsfoot are even harder to remove).

Go ahead and use all that mulch!

Very important: a tractor will only make things worse. It's impossible to remove them that way. Because the tractor will of course mess up with your soil structure, and it will cut the roots of the lupins making more lupins. Doesn't work, we tried it here. They just come a before. They even grow under pavements and walking lanes, walls of houses.

Best is to use a shovel or small machinery to uproot them, and then remove all roots manually, over the course of the next months and few years. Be sure not to let them go to seed. Changes are they are already growing widely around your property. They spread very fast in here by their seed (when dry the seed is released in a violent way, through a spiral tension inside their pod - a very clever strategy). Also, the lupins are very hardy. I would still keep a patch of them to use as a compost mulch for your garden. Wasting that resource would be unclever. But do NOT let them go to seed. Just graze them, and they will only spread by their roots, which is not so much. Much worse by their seed.

More: they do not penetrate inside a forest. They dislike shade. But only with thick forests (poplar and spruce), they still invade birch and willow forests. They also do not grow so well where land becomes a wetland. There you have mostly angelica and willows, in balance with the lupin. They also do not grow in slopes and mountains, because their seeds cannot propagate to the tops of the steepy Icelandic mountains, but they are invading well into the desert interior, everywhere except mountains and thick forests. Every year a few more dozen meters (as said they spread by throwing their seeds far away). In dry and flat land, mostly andy soils, this is easy for the lupins. Hope this was useful for you.

Interesting... I have Brenda's experience. I was growing Lupinus albicaulis and Lupinus arboreus in gallon pots. They overgrew to pots, and I didn't have a place I wanted to put them, so I cut them back and kept watering them. Half of them died. Research the species.

Thanks all for your input!

Seems like there are very different varieties with different hardiness etc. I think we have the wild invasive kind here too.
You can really see it spreading.

Paulo: Great info! You suggest digging up their roots by hand. This seems like soo much work You dont think covering with something would work at all?
I dont really know how perennials work with their root system... Do they "live" underground even if the plant is not being able to develop over ground or do the roots
break down eventually?

I have begun removing the seeds, so I will have LOTS of them. I will look into the possibility of mailing some abroad if there is interest.

Roots and shoots are connected. The roots provide water and nutrients to the shoots, the shoots provide sugar/sun energy to the roots. The energy of the plant (in terms of nutrient/sugar) shifts over the course of a year. In spring stored energy flows from the roots into the new growth and flowers, and seed, and is complemented by new energy captured by the leaves. After floweing, energy begins to flow back into the roots (as well as the seeds which become a mobile energy reserve for the plant). The strength of these flows depends on the species and the environment, and this is a simplification, because energy and materials are flowing all over all the time, but the pattern is true.

That is why cover crops are tilled under at flowering when top growth has peaked. It is also why cutting at flowering but before seed is viable is the most effective time for controlling unwanted plants. Some plants are always ready for disturbance, by retaining a large energy/nutrient reserve in the roots. Once ALL shoots are gone, a plant is operating on reserves (like a biochemical battery). If it is cold or dry, a plant can sleep (go dormant) and live off of reserves for a very long time. If it is warm and moist, plants will try to grow shoots. Some plants (like our Himalayan blackberry, Rubus procerus), you need to remove all shoots for 2 growing seasons to kill it, and this has been done with black landscape fabric.

I wonder about pigs? I have a vague memory that lupine makes poor browse, but a don't know about the roots.

The other way would be to not worry about the ground layer, and just use the lupine as a mulch crop as you move over time into a tree and large shrub system... edible forest or woodland vegetation. It would be interesting to observe at what level of canopy closure that the lupine becomes less dominant. It also appears the the lupine dominance is seasonal. Lupine are strong in spring, but allow other species to compete, as energy flows back to roots and seeds. The soil is likely loaded with lupine seeds, which I suspect are very durable (given that some species come back after forest fire!). So if you kill the existing plants, you will still have new recruits every time there is a disturbance.

Also, if this species is connected underground (not common among Lupines, but I don't know your species), you have a different problem, as there is no 'individual' but rather a energy trading network that is more difficult to disrupt.

Hi Paul, here in Iceland I have been observing the lupins for a long time.

They are a introduced species but apparently they can't enter a forest of aspen, poplar or spruce, since it is a thick canopy and shade.

But they invade easily a birch forest. Birch forest has plenty of sunlight reaching down, as trees as not very much thick, broad or tall. They also enter a forest of pines, rowans or other kind of small trees.

However I agree, they seem to have seasonal dominance. After summer, they stop growth (energy goes to the roots) but the trouble is their already thick cover will make difficult for other plants to grow through it. In early spring the lupins start rather slowly, and some plant can grow faster and taller than them (here this applies to angelica or meadowsweets). Seedlings also appear more often in disturbed or sandy soils.

Paul Cereghino wrote:Roots and shoots are connected. The roots provide water and nutrients to the shoots, the shoots provide sugar/sun energy to the roots. The energy of the plant (in terms of nutrient/sugar) shifts over the course of a year. In spring stored energy flows from the roots into the new growth and flowers, and seed, and is complemented by new energy captured by the leaves. After floweing, energy begins to flow back into the roots (as well as the seeds which become a mobile energy reserve for the plant). The strength of these flows depends on the species and the environment, and this is a simplification, because energy and materials are flowing all over all the time, but the pattern is true.

That is why cover crops are tilled under at flowering when top growth has peaked. It is also why cutting at flowering but before seed is viable is the most effective time for controlling unwanted plants. Some plants are always ready for disturbance, by retaining a large energy/nutrient reserve in the roots. Once ALL shoots are gone, a plant is operating on reserves (like a biochemical battery). If it is cold or dry, a plant can sleep (go dormant) and live off of reserves for a very long time. If it is warm and moist, plants will try to grow shoots. Some plants (like our Himalayan blackberry, Rubus procerus), you need to remove all shoots for 2 growing seasons to kill it, and this has been done with black landscape fabric.

I wonder about pigs? I have a vague memory that lupine makes poor browse, but a don't know about the roots.

The other way would be to not worry about the ground layer, and just use the lupine as a mulch crop as you move over time into a tree and large shrub system... edible forest or woodland vegetation. It would be interesting to observe at what level of canopy closure that the lupine becomes less dominant. It also appears the the lupine dominance is seasonal. Lupine are strong in spring, but allow other species to compete, as energy flows back to roots and seeds. The soil is likely loaded with lupine seeds, which I suspect are very durable (given that some species come back after forest fire!). So if you kill the existing plants, you will still have new recruits every time there is a disturbance.

Also, if this species is connected underground (not common among Lupines, but I don't know your species), you have a different problem, as there is no 'individual' but rather a energy trading network that is more difficult to disrupt.

Henrik Hellman wrote:Thanks all for your input!

Seems like there are very different varieties with different hardiness etc. I think we have the wild invasive kind here too.
You can really see it spreading.

Paulo: Great info! You suggest digging up their roots by hand. This seems like soo much work You dont think covering with something would work at all?
I dont really know how perennials work with their root system... Do they "live" underground even if the plant is not being able to develop over ground or do the roots
break down eventually?

I have begun removing the seeds, so I will have LOTS of them. I will look into the possibility of mailing some abroad if there is interest.

One thing for sure is that they do grow here as a weed as they say. Oh, i live in Göteborg. I'm an American transplant. I'm not real sure what or how much you want to do. Just remove what you want starting out small than then go from there. I'd wait and start in late April. You know how long it takes for spring to actually get here. This summer BTW was the lousiest growing season with cool temps and almost constant on and off rain.

Coming from the Southwest USA I can tell you it's been hard for me living here. I'm use to growing things all year long. With there being so much wet, it's discouraging to be outside very much. Heck, it's this climate that actually forced me to sit down and write my experiences on blogs. If not for that I would have never done it and that would have been a shame because I've been very successful in re-establishing damaged habitat through replication of just how natural systems work. That's why conventional science blows me away. They have important studies for which are loaded with clues, but they opt for conventional methods which bastardize the health of our planet. Of course conventional science is in the power and wealth acquisition business anyway.


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Kevin Franck wrote:
Oh, i live in Göteborg. I'm an American transplant. I'm not real sure what or how much you want to do. Just remove what you want starting out small than then go from there. I'd wait and start in late April. You know how long it takes for spring to actually get here. This summer BTW was the lousiest growing season with cool temps and almost constant on and off rain.

Small world, I'm not far from Göteborg, 10 miles south east! I can imagine growing season wasnt so good this summer. Greenhouses do make a lot of sense here
You have ablog you said, you have a link maybe?

Anyways... The plan is to turn this lupin-invaded area to a place for growing lots of veggies, fruit trees berries etc.
I'm still very confused on how to get rid of all these lupins. I'm very curious about sheet mulching, maybe I'll try that on a smaller area and see if it keeps them down. I can also dig up the roots on another area and see how it works out...

Ultimately permaculture is about the relationship between you and your land, so doing some experiments, and observing and interacting, makes a lot of sense to me.

Personally, I would be getting the exact ID of the species of lupin you have and then researching that species. Lupins vary quite a bit in what they do, and knowing the exact species will help with understanding what your options are.

Henrik Hellman wrote:

Small world, I'm not far from Göteborg, 10 miles south east! I can imagine growing season wasnt so good this summer. Greenhouses do make a lot of sense here
You have ablog you said, you have a link maybe?

Anyways... The plan is to turn this lupin-invaded area to a place for growing lots of veggies, fruit trees berries etc.
I'm still very confused on how to get rid of all these lupins. I'm very curious about sheet mulching, maybe I'll try that on a smaller area and see if it keeps them down. I can also dig up the roots on another area and see how it works out...

My blog links are in my signature, or should be. I'm actually over in Hissingen in Biskapsgatan. I did a series of posts in my Timeless Environments blog on Götebord Botanical Garden's Ökenliv (Desert Life) theme this year. I actually found ways of creating a Faux Desert theme landscape for Sweden. Folks in the southwest would recognize some of the plants I chose and why I chose them. Also did some posts on Biological Soil Crusts which one normally associates with desert, but the reality is they are everywhere, even here in Svenskland.