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Plant Doctor Archive
Planting in pots

I
DON’T have room for a vegetable garden, so I’m growing lettuces,
strawberries and herbs in pots. When it rains, it splashes potting
mix all over the deck. Can I use white limestone chip as a mulch
or will it affect my plants? If I can’t, would plain gravel be ok?
IN theory, limestone chip could
raise soil pH, but decorative white limestone chip is unlikely to
have much effect as it’s harder and far less soluble than garden
liming products. I would have no hesitation in using it as mulch
around most plants, including your strawberries, vegetables and
herbs, in pots or in the garden. You could wash it first to remove
any lime dust and, to be on the safe side, avoid using it around
acid-loving plants such as azaleas, ericas, kalmias and gardenias.
You can also safely achieve the same effect with other materials such as river pebbles or coarse pumice. All will not only keep your plants clean but deter weeds, conserve moisture and give your pots an attractive finish.
To maintain a fresh new look and remove unsightly algae, you could occasionally soak your pebbles or chip in a weak bleach solution (one part bleach to 20 parts water) for 20–30 minutes then rinse before putting back on your pots.
Weekend Gardener, Issue 132, 2003, Page 28

