They are all natural, of course you can... I would limit the amount of ash due to high alkaline properties.
Ashes have a high alkaline content, trace amounts of potassium and calcium, making them great for numerous projects around the house. When you collect ashes from the fireplace, ashtrays and grill, reserve the ashes and recycle. Cigar and cigarette ashes are handy too
Feed ashes to plants to encourage blooms. Counteract acidic soil by sprinkling it with ashes for plants like clematis, lilac and roses that love alkaline soil.
Read more: How to Recycle Ashes | eHow.com
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