Hi

I´d like to plant crepe myrtle in the corner of a raised bed which borders the garden (see attachment for a visual) . I need to fill the raised beds with soil, what type would you recommend? We are based in Madrid, Spain. Any other hints and tips would be very appreciated!

Also, as I love this plant, I´m thinking about planting more along the raised bed...or would this be too much?

Many thanks!

Is your raised bed open at the bottom or closed all the way around? In other words, will the roots be able to penetrate into the existing garden soil?

porkpal said: Is your raised bed open at the bottom or closed all the way around? In other words, will the roots be able to penetrate into the existing garden soil?

They are open at the bottom but the soil is poor - clay with sand (I think - I'm not very experienced!)

If you fill the raised area with a different soil, water will not pass freely down from one soil to the other and the plants' roots won't either. I would at least incorporate a significant amount of the native soil in the mix you use to fill the planters and loosen the clay at the bottom.

IME with crapes, they are not something that should be placed where you will disturb the soil around the roots for other gardening. Damaging a root will cause suckers to sprout up, in addition to the random suckers that pop up for no reason. They are wonderful little trees but need a very large area to themselves.

Long term, most attempts to grow trees in raised beds that I've seen have ended in failure. Tree roots naturally want to extend laterally more than downward. In a restricted area they will circle and become crowded and/or damage the bed walls. How deep and wide will the bed be? What is it made of? Is the back portion a wall covered with vines? Have you run this plan by a professional landscaper?

purpleinopp said: IME with crapes, they are not something that should be placed where you will disturb the soil around the roots for other gardening. Damaging a root will cause suckers to sprout up, in addition to the random suckers that pop up for no reason. They are wonderful little trees but need a very large area to themselves.

Thank you for replying, I had no idea. So you wouldn't recommend crepe in a raised bed at all? I really love this tree and it's one of the few flowering trees I like that would do well in Madrid. If it had a larger area to itself I'm wondering if I could plant jasmine a bit further away and use it as ground cover. Could that work?

If the pic is the actual spot in question, I would put CM right in the middle of the grassy area, maybe. ...is it a rooftop garden?

This is the garden, it's artificial grass. The corner of the raised bed is 1 metre X 1 metre (soil area, not including concrete. The idea was to put a small tree here and I was hoping for crepe myrtle. If it won't do well I wonder if anyone could recommend sone alternative flowering trees that can cope with hot summers (40°c), full light and cold winters (a few degrees lower than freezing at the coldest). Or indeed anything else you would do with this space! Thank you so much in advance!

NMoasis said: Long term, most attempts to grow trees in raised beds that I've seen have ended in failure. Tree roots naturally want to extend laterally more than downward. In a restricted area they will circle and become crowded and/or damage the bed walls. How deep and wide will the bed be? What is it made of? Is the back portion a wall covered with vines? Have you run this plan by a professional landscaper?

Currently we have nothing in the raised beds (see photos in a post below). They are made of bricks and concrete, and at the back the fence sits on a wall of concrete. There is soil below. The design was done originally by a landscaper. I was told crepe would be ok here as it's not a large tree, but it sounds like that not be the case!

I would defer to the landscaper, which I'm not, although the space seems very small for any type of tree. There are dwarf and semi-dwarf crepe myrtles that top out between four and eight feet, which I imagine have proportionately smaller root systems. Otherwise, perhaps something more like a shrub? ... although I suspect that's not the look you're going for. Maybe more suggestions will be forthcoming.

That fencing looks ideal for a climbing, flowering vine.

On the other hand, Crape Myrtles are often used as plantings near buildings here as their roots - supposedly - are not invasive/destructive. Check with your landscaper.

Below is a pic of my crepe myrtles which are in a raised bed with open bottom into hard pack clay soil. Every year I use fertilizer plant steaks place around the root ball . They are tough plants dealing with -12F and over 100F temps. They are on a auto soaker system.

Beautiful!

Excellent Bea. Thank you.

So beautiful! Do you mind me asking how wide your raised beds are?

15- 25'- 35' wide in several of the areas where the small tree collection is located.

And how deep?

3-6" only used mushroom compost in the entire garden. Available in rock/soil yards. I just ordered dump truck loads to drop piles around the area.

Maybe there are dwarf cultivars, but I don't think of CM as a small tree. The base of ours is too big for one person to wrap their arms around.

This pic is from 2021, it's bigger now.