Planting Lupin seeds - what is best compost

[HopelessGardener]

I am going to plant Lupin seeds in pots in October.

What is the best compost to use? Last couple of years my efforts at growing Lupins from seed have been a disaster. Used multi-purpose compost.

 

[Sheal]

I've never had a problem germinating Lupins but you could try soaking them for a couple of days first or using some sandpaper to scratch the surface. It doesn't need to be the whole surface, just enough to weaken a spot on the outer shell for the roots to break through.

Seeing that you're in England I'm assuming you have to use peat free compost. This is hopeless for starting most seeds and restricts growth of seedlings. If you have some home produced compost, that would be better.

 

[HopelessGardener]

Yes the compost was peat-free. I did however find some peat in a small garden centre the other day. Not sure it was the peat of old, thought peat was very black in colour? Been so long since I'd bought a bag of peat as not available to consumers for at least 15 years.

The Lupins I've tried growing from seed the last couple of years grew to about 6 inches tall and then stopped progressing. Some even started going red. None of them got anywhere near the flowering stage.

 

[Sheal]

Scotland hasn't banned peat yet and I've bought this recently at a local Garden Centre, it's very good. I've been told you may be able to buy it in Lidl but I can't confirm that.

Moorland Enriched Multi Purpose Compost 40 Litre

specially formulated mixture of high quality peat, base fertilizer and wetting agent giving an open texture for plant roots to establish

barrsgardencentres.co.uk

The black peat of many years ago I believe came from the south west - Somerset. In more recent years peat has been brown and mostly imported from Ireland.

I assume you potted the young plants on into fresh compost individually? The redness implies too much fertiliser or pest damage.

 

[HopelessGardener]

I had just popped the lupin seeds into the pot and left it. Pots about 6 inches tall. Watered regularly and would have had some seaweed liquid feed applied just the once maybe twice. But have been trying the last 2 years and had planted lots of them. Not one grew into a full-sized plant in flower, nowhere near. Was so disappointed. Seeds were from different packets/brands, Russell Mix (Wilko) and Tutti Frutti (T&M).

But 10 years ago I had no problem growing them - you popped in a seed and it grew as expected.

This month, I will soak the seeds first, use the peat for some of them and will get a seed potting compost for others. Should I plant them in smaller pots or plugs to start with?

 

[oneeye]

I like to start seeds in small dixie cups with four holes punched in the bottom. After a few weeks of growing I up pot into a larger one-gallon pot or #5 pot. If you use a peat-based mix, you are using a soil-less mix that needs to be supplemented with nutrients. If the pots don't have enough nutrients, you won't get any flowers in the end.

Theres two different ways you can supplement nutrients. One is use a slow-release fertilizer like Osmocote 15-15-15 pre-mixed with the potting soil. You and add a couple of teaspoons to the one-gallon pots of soil before up-potting. The other is to use a water-soluble liquid fertilizer a few times with water to keep the EC high enough to support flowers.

 

[Sheal]

I had just popped the lupin seeds into the pot and left it. Pots about 6 inches tall. Watered regularly and would have had some seaweed liquid feed applied just the once maybe twice. But have been trying the last 2 years and had planted lots of them. Not one grew into a full-sized plant in flower, nowhere near. Was so disappointed. Seeds were from different packets/brands, Russell Mix (Wilko) and Tutti Frutti (T&M).

But 10 years ago I had no problem growing them - you popped in a seed and it grew as expected.

This month, I will soak the seeds first, use the peat for some of them and will get a seed potting compost for others. Should I plant them in smaller pots or plugs to start with?

Lupin seeds can be fickle, sometimes they will germinate, other times not. Try up to half a dozen in a 1 litre pot and cover them with a plastic bag. When they appear remove the bag and pot on when needed. Condensation within the bag should keep them watered until it's removed. Don't feed them. Seeds and seedlings do not need feeding. Bought compost has a nutrient supply for up to six weeks and when they're potted on new compost will supply the same.

 

[Sheal]

Theres two different ways you can supplement nutrients. One is use a slow-release fertilizer like Osmocote 15-15-15 pre-mixed with the potting soil. You and add a couple of teaspoons to the one-gallon pots of soil before up-potting. The other is to use a water-soluble liquid fertilizer a few times with water to keep the EC high enough to support

Oneeye, here in Britain all bought multi purpose compost and topsoil has nutrients added on production which lasts up to six weeks, so there is no need to add fertiliser. If it is added then it has a detrimental effect on seeds and seedlings and will force them to outgrow their strength.

 

[dirty hands]

Out of a pack of seeds I got 6 plants in the ground. Then lost 3 one at a time. The last 3 were doing OK then the deer ate them.
They also ate my 2nd year holkyhocks which are coming back.

 

[Sheal]

I had Lupins in my previous garden and deer didn't touch them - strange. I wouldn't have thought different breeds of deer have different tastes in what they eat.

 

[dirty hands]

It was just the young leaves. It hadn't flowered yet.
The deer here eat a lot more than I thought they would. They are very aggressive.

 

[dirty hands]

---

These are or were the lupine and the hollyhicks. Both were completely stripped of leaves.

 

[Sheal]

I wonder if it's worth trying again and protecting the plants with netting or similar until they're mature?

Here you are @dirty hands - not a leaf harmed. I planted them out at about 1ft high. Perhaps it may be something to do with the breed of deer. My visitors were Red deer.

 

[dirty hands]

I put wire fencing around them but I waited too long. Had another junior giant arbovitae get rubbed by the deer too. Its really a challenge here living by the river and a lot of wooded areas.
I spray a lot of plants too.

 

[dirty hands]

I wonder if it's worth trying again and protecting the plants with netting or similar until they're mature?

Here you are @dirty hands - not a leaf harmed. I planted them out at about 1ft high. Perhaps it may be something to do with the breed of deer. My visitors were Red deer.

View attachment 111688

That looks really nice. Maybe someday I can fence off an area to grow more plants.