Newbie compost questions

[grahamfx]

Hi, new to alpine gardening and to the forum, I have a few compost questions

I'm constructing an alpine area in the garden approx 3m x 2m, I've put in a base layer of rubble and stone, now ready to cover with compost and
then grit on the top

The compost mix I was planning was 2 parts leaf mould, 2 parts compost, 1 part grit and 1 part sharp sand is this ok for general alpine growing ??

For the compost part of the mix am I better buying multi-purpose compost or using my own from my compost bins ?? Mine might have weed seeds in
but it's getting covered with grit and any weeds should be easy enough to remove ??

Thanks for any help !!

[Ian Y]

Hi, new to alpine gardening and to the forum, I have a few compost questions

I'm constructing an alpine area in the garden approx 3m x 2m, I've put in a base layer of rubble and stone, now ready to cover with compost and
then grit on the top

The compost mix I was planning was 2 parts leaf mould, 2 parts compost, 1 part grit and 1 part sharp sand is this ok for general alpine growing ??

For the compost part of the mix am I better buying multi-purpose compost or using my own from my compost bins ?? Mine might have weed seeds in
but it's getting covered with grit and any weeds should be easy enough to remove ??

Thanks for any help !!

Welcome to the forum Graham I hope we can help with your new alpine area and that you will share pictures as it progresses.

The proportions for your compost mix is a good start what you need to achieve is an open gritty compost that allows surplus water to drain away quickly so the amount of grit you need to add depends on the nature of the compost and the sand. When you make your mix take a handful and squeeze it in your hand it should form a loose ball that will fall apart when you poke it or shake your hand if is does not add some more grit until it does. Another way you can gauge the mixture  is to fill a pot with your mix flood it with water and see how quickly it drains away.
I would favour using your own garden compost if it is well rotted down -  leafmould is also very good if you have that.

[grahamfx]

Welcome to the forum Graham I hope we can help with your new alpine area and that you will share pictures as it progresses.

The proportions for your compost mix is a good start what you need to achieve is an open gritty compost that allows surplus water to drain away quickly so the amount of grit you need to add depends on the nature of the compost and the sand. When you make your mix take a handful and squeeze it in your hand it should form a loose ball that will fall apart when you poke it or shake your hand if is does not add some more grit until it does. Another way you can gauge the mixture  is to fill a pot with your mix flood it with water and see how quickly it drains away.
I would favour using your own garden compost if it is well rotted down -  leafmould is also very good if you have that.

Hi Ian thank you for your reply, I have loads of leaf mould, would it work without any compost at all, 4 parts leaf mould, to 1 part sand and 1 part grit, would be guaranteed no weed seeds then ??

[Ian Y]

Yes that would work but remember that leamould will break down more quickly making your mixture leaner in a few years time.

There is an alternative I could suggest depending on the depth of the bed add a layer of your garden compost, mixed with some grit if you think  necessary, over your base layer of rubble then make make the top 30cms plus leafmould, grit and sand. That way the plants are in a well drained top layer and can send their roots down into the garden compost layer. 

[grahamfx]

Great thanks for the help

[Maggi Young]

Welcome to the Forum, Graham - and happy  making and  planting !

[David Nicholson]

Welcome Graham you will always get good advice here. Looking forward to seeing your pictures when you are ready.

[fermi de Sousa]

Hi Graham,
Welcome to the friendliest forum
A question I would ask is "what do I want to grow here?" - and also where have you situated the rock garden.
The mix you are describing sounds to me to be best suited for most plants but some bulbs (especially some of theSouth African or Mediterranean species) would probably appreciate more grit.
The covering with grit s important to help with water conservation and for giving some cohesion to the garden.
All the best - a new garden is always exciting!
cheers
fermi