After 5 years the root systems have probably spread to such a degree that
going in and completely rejuvenating the soil might be a good idea. I would
pop all the perennials out (dividing those that need it at the same time),
and then work via shovel and hoe a great deal more organic material,
compost, shredded leaves, etc. into the existing soil. I would break up
and/or remove big fibrous root masses and replace with new soil, then
replant the perennials.

Dave

"Laurie" wrote in message
et...
I have 16 wooden planters on my deck. I have horses wandering around the
acreage who would eat anything planted down on terra firma, so my
gardening
is pretty limited to these planters they can't reach.

They are 3' X 1.5' in size. They are 5 years old now and the soil level
has
dropped enough that I want to raise it. But I have a lot of perennials
like
lavender, daisies, etc that were cut back properly and still live here and
there in the planters. In the past, I would buy mainly annuals to
supplement
the resident perennials. So, experts....what would be the best way for me
to
raise the soil level without just uprooting everything and starting all
over? Do I just go out now and buy enough soil to pour over the top, or do
I
wait until the perrenials get high enough so they wouldn't be "drowned" by
the addition of the soil? Or something else altogether??

Thanks for any ideas

Laurie