Is this the normal colour for new growth as plant leaves are normally green and lime.
New leaves emerging may be lighter in color or yellowish. Perfectly normal!
50 Hedges planted 12months ago. Seemed to be doing very well but have begun to go brown. Anyone any ideas please. Flowers still coming through
I see signs that the soil may remain too moist. This will suffocate roots if it doesn't have enough time to dry out some between waterings. This can cause diseases that could persist after the soil dries.
If the area remains moist, then you might consider moving the shrubs to another location. If the area can be let to dry, then treating with a fungicide may help. Be sure to test nutrient levels an pH to rule out those factors.
Because this genus tends to be invasive, I would suspect a major issue. This may even require assistance from your local extension services.
https://www.gardeningknowhow.com/ornamental/shrubs/elaeagnus/russian-olive-information.htm
https://www.gardeningknowhow.com/garden-how-to/info/what-is-extension-service.htm
https://www.gardeningknowhow.com/garden-how-to/info/using-fungicides-in-garden.htm
https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/soil-ph-plants.htm
https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/testing-soil.htm