It would appear that this plant has either psrtially died or had had the wind at it?
My garden was watered with sandy water but found that it also had salt in it; what if anything can I do to the soil, as it has killed a few of my plants.
Chelating the soil can be done, but it not carefully, it can lead to more problems.
Citric acid is a common chelator. Using this at .02 percent along with dextrose at about .04 percent per gallon can help reduce salt concentration, but proper soil drainage will, ultimately dictate your success here.
Here is an article that will help you with the salt content of soil, and removing it:
https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/reversing-soil-salinity.htm
Small pond. Newts were in it in June. Is the green stuff frog spawn?
Unfortunately, your photo did not come through. It could be anything from algae to frog, to newt spawn, or potentially other things as well!
I did some landscaping in early June. All the plants did great at first but now they look horrible. I’ve treated them with bug/disease spray and feed, but they are t doing any better. Please help!
It looks like a combination of heat stress and overwatering. This is common when planting during undesirable times of the year.
Planting should be done in Autumn or Spring to avoid this.
Form here, I would use a fungicide. This article will help:
https://www.gardeningknowhow.com/garden-how-to/info/using-fungicides-in-garden.htm
Checking the moisture level will be a little difficult since there are stones on top of the soil. Since you will not be able to see the moisture level, visually, a moisture meter will be needed to check and make sure that the soil is completely dry down to about 3 or 4 inches between watering. This will ensure that the plants to do contract a disease from wet soils.
Here is an article that will help you to use a moisture meter:
https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/testing-moisture-in-plants.htm
This article will help you with transplant shock:
live in Vt. Last year flower garden & brick border suffered frost heave, saved some flowers but all bricks had to be reset 2 inches down again.....can these be covered with something over the winter to prevent the heaving?thanks
Protecting the soil from heaving should also help the bricks. Here's how:
https://www.gardeningknowhow.com/garden-how-to/mulch/mulching-plants-in-winter.htm
I have a natural underground spring that runs through our garden, unfortunately it seeps through a wall into our neighbours garden which is lower causing quite a flood. I would like to solve this problem but use the water. Could I somehow fit a hand pump ( i don't really want a pond if I can help it) Thank you
This will be something for your local authorities on the subject, for your country. There may be codes to follow and differences in laws from your country to ours here in the US.
plants were all healthy
That damage can be attributed to herbicide damage, but it only if the onset was sudden. If this had been developing over more than a week or so, then this is not herbicide damage. If it happened within a matter of days, or within a week, then you can assume that it is herbicide damage.
This article will help you to give the plants their best chance after such an incident:
https://www.gardeningknowhow.com/plant-problems/environmental/herbicide-plant-damage.htm