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Wood Ashes

Question:

I have a stock pile of wood ashes from my fire place. I've heard these are good for my garden but am unsure how to use them. Can you help me with this?

Answer:

Everyone enjoys the warmth of a fire on a cold day. But after you've built a few, the ashes begin to accumulate. So what can you do with them? Well, they're ideal for the garden, if you apply them properly. And hardwood makes some of the best wood ash for the garden.

These ashes contain nutrients at about 1 percent phosphorous, 5 percent potassium and small amounts of other elements that our plants need to bloom more and establish a stronger root system. These can be of great benefit to your garden depending on your type of soil. But before using ashes there are some things that you might find helpful.

First, you should only apply these if your soil pH or acidity factor is less that 7 on a soil test. If you're not sure what the pH of your soil is you should have it tested.

Wood ashes will cause your soil chemistry to change. They'll sweeten the soil. This is great for a lot of vegetables like broccoli and collards, as well as ornamentals such as lilacs and peonies but be careful. Sweet soil can be the kiss of death for many acid loving plants like azaleas, rhododendrons, camellias and Japanese iris.

Wood ashes should not be considered a complete fertilizer. If you want your plants to be nice and green, you'll have to add nitrogen. There's no nitrogen in ashes.

It's recommended that only 10 to 20 pounds of wood ash be applied per 1000 square feet each year. So as you can see, a little bit of wood ash goes a long way.

I like to apply ashes to my vegetable garden in the winter because they should never come in direct contact with seed or the roots of plants. This can cause a salt burn from the potash in the ash. By applying ashes before the planting season begins and working them into the soil you can avoid any risk.

You can also apply wood ashes to your lawn at a rate of about 15 pounds per 1000 square feet. But if your lawn grasses are actively growing make sure the ashes are well watered in to avoid burning the turf.

And for keeping those slugs away, pour your ashes in a ring around your plants. The slugs will not cross it. But when it rains, you'll have to apply them again.

Plants that Respond to Wood Ash:
Ornamentals:
Peonies, Tall Bearded Iris, Lilac, Lavender, Clematis, Columbine, Lupine, Santolina, Rosemary, Baby's Breath, Oriental Poppies, Daffodils.

Vegetables/Fruit:
Apples, most root crops, Collard, Broccoli, Cauliflower, Brussels Sprouts, Cabbage.