Are they all standard size trees? I think I would keep them in pots so A) they stay smaller, and B) you can bring them into the garage during the winter. You could line the pots up against the wall, put them on a drip system, and you should be fine. I got these tiny citrus at Walmart 2 years ago like you, cheap! 2 are in the ground, and 2 are in containers about 16" across. This is their second year, and the grapefruit is getting huge in it's pot. There is no difference in size between the orange and the other two planted in the ground. Mine are Semi Dwarf.

We get big winds here also, but it hardly freezes. I have Christmas lights to help warm them up IF we get a freeze.

Good luck!

They are all dwarf/semi dwarf. Unfortunately, I do not have a garage so that isn't an option.

We get several freezes every year and last year I lost my Meyers lemon even with Christmas lights - that's why I thought maybe keeping them flat on a protected south wall with the option of anchored burlap might work.

I really need to know if there are issues with spacing them only 24" - 30" apart. Any help would be appreciated!

>>> I really need to know if there are issues with spacing them only 24" - 30" apart.

Well, not directly. Are you expecting more than a handful of fruit from each? Although never recommended, citrus *can* be planted very closely together if you plan on pruning them hedge style or if you only plant two real close, then let them grow away from each other. But IMO you're trying to fit them too close.

You didn't state this, but are you trying to single-level espalier on your 18" concrete wall?

If you go out there and draw on the wall a simple shape of the espalier form you are growing -- you'll realize 24" is a very, very small space. I frequently read "if you don't have much space, try espalier". But what they are really saying is if you have a "LONG rectangular size space". Without depth, you need more space for length or height. Even 30" apart means approx. 14" per branch, more like 9" once the tree thickens trunk and branch crotches reduce fruiting wood close to the trunk.

You could plant 48" from each other and espalier the branches at ALTERNATING levels. For multi-level, leave a bit more space vertically between branches than you would normally. This way you can have almost the full 48" for each branch, as each tree will grow into the other's space -- like when you mesh your fingers from one hand into the other hand.

You probably already realize but citrus fruit on the prior year wood. In many cases they will push out young branches and flower on them later, for more fruit production you can keep them like "short spurs", which is why I'd allow for more room when meshing them.

In any case, I'm not an espalier expert but I do understand your situation. That was such a great deal I probably would've done the same! But I'd just grow half of them in containers and espalier the rest without trying to go too close together. Or just bite the bullet and call them "gifts" that you couldn't turn down.

Our area doesn't carry ANY satsuma other than owari.

Honestly, I would try espaliering only the 4 satsumas against the south wall. I would plant them 1-1.5 feet away from the wall and at least 6 feet spacing between them. By espaliering, you are already eliminating two directions of growth (north and south)...if you reduce spacing any more than that, you would be reducing two more directions of growth (east and west).

I would seriously doubt that lime, lemon drop, meyer lemon, or orange would survive outside, even against a south wall. The lime and lemon drop will stay small enough that you can pot them up and bring it inside.