North facing shady garden, need permeable options

[MojoMoon]

I have a small, shady, North facing urban garden (or more a yard at the moment) which is completely with concrete paving stones laid directly into the earth

They rapidly go green and slippery moss covered because when it rains the water pools on the stones and takes a long time to dissipate.

I plan to put on tiered raised beds around the edge of the garden and to keep a small area of hard standing at the back corner which gets a bit of sun for a very small chair and table. There is also a bike shed in the other back corner.

What would be the best option for a permeable ground cover to lay between the raised beds? Water needs to drain away better. Needs to not be too attractive for cats to poo in. Will need to withstand bicycles being rolled over it to the shed.

Any suggestions wise gardeners? This is my first garden.

You can go for gravel - over a membrane if you want, but personally I would just put it direct onto the soil after lifting the slabs. The trouble with the membrane is the gravel just slips and crunches around on it and travels into the house, the toughest weeds can grow through it, and over time stuff settles on it and weeds grow in that. A good layer of gravel direct onto the soil will bed in better although it will need topping up from time to time. Alternatively, stepping stones through Mind Your Own Business can be very pretty.

I agree with @olderbutwiser , a decent layer of gravel on bare soil or stepping stones, and avoid using membrane. If you wanted a firmer surface than normal shingly gravel, you can get self binding gravel, which might work better for bikes and weed suppression. You could even crush the existing slabs and use the resulting aggregate.

You will get plants (weeds) growing through (if perennial) or self seeding, but I would dig out any perennial weeds before laying the gravel, and self seeders are easy to pull up as they appear (you might want to leave some self seeders though, depending on what they are).

As olderbutwiser said, membrane is limited in its effectiveness at suppressing weeds. Persistent weeds will just grow through it, and eventually you get a layer of organic matter building up on top of the membrane that weeds can grow in. Membrane creates plastic pollution too, so I honestly can't see the point of the stuff.

Thanks both - I had assumed membrane was an essential so good to know it causes issues too.

I had never heard of Mind Your Own Business but it looks nice where stepping stones are set between the greenery. Would it need a lot of watering during summer to stay green?

I was going to say gravel too until you mentioned the cats...they do love to use gravel as a litter.

You could try a lawn alternative. My favourite for shady areas is lippia/phyla nodiflora. It will lose its leaves if there is a hard frost but they will come back, and will stay evergreen in a warmer area (as is often found in urban gardens).

If you walk on it a lot it will become tight and stay low, in low traffic areas it becomes taller. You don't need to water it except every couple of weeks if the summer is hot and dry. It can survive flooding and drought.

Thanks.
If I go for lippia or mind your own business or other lawn alternatives, would I just lift the pavers and plant them straight into the soil and then wait for them to spread? If the soil has been under pavers for 30 years, should I add something to it?

You should definitely improve the soil if you can - some well rotted manure mixed in will do whatever you plant in a world of good.