In many states, great piles of sawdust are going begging. Some of them, aged and well-rotted, are located in country sawmills. Others, both old and fresh, stand high in local lumber yards where lumber is cut for retail trade.
It may be hard to ask if you can carry much of this sawdust from the mill to your garden. You will probably have to pay for hauling it home in large quantities. However, a pick-up truck can carry enough for a summer’s work in a small garden or flower bed.
You may pay between 3 and 6 dollars for a pick-up truckload delivered to your garden. In many cases, the cost of loading and hauling will far exceed that of the sawdust.
Compared to what the sawdust will do for your garden, it is cheap at twice the prices listed. In addition, it is clean, light in weight, and easy to handle.
You will find that it keeps the moisture in the soil, discourages weeds, and when it is worked into the soil at the summer’s end, it improves the texture of the soil.
Fertilizing Sawdust-Mulched Garden
Fertilizing the sawdust-mulched garden is just like any cultivated garden except for treating areas that may show nitrogen deficiency. This lack of nitrogen is suspected when plants turn light green or yellow.
A chemical reaction with the sawdust makes the normal nitrogen in the soil unavailable to plant life.
If, after using sawdust, you find the leaves and stems of your plants turning yellow, use an extra shot of fertilizer that contains usable nitrogen.
Irrigation or the next shower after applying nitrogen fertilizer will produce quick improvement. Nitrate of soda or ammonium sulfate will do the job when about two pounds are used to 100 feet’ of row.
Ammonium nitrate may be used more sparingly, about one pound per 100 feet of row.
Avoid Nitrogen Deficiency
Avoiding this nitrogen deficiency is the only precaution necessary in using sawdust as mulch. However, care should be taken that the roots of plants that normally grow close to the ground’s surface are not smothered or allowed to rot.
Varying depths of sawdust should be used because this mulch can do several different things for your plants.
If you want to control weeds, you will use more sawdust than you will if you want to hold light moisture around new seed sprouts. The table, opposite page, shows suggested depths.
Sawdust Use As Mulch
For a long time, there has been a hesitancy in using sawdust as mulch because fresh sawdust was thought too acidic for many plants. Walnut sawdust was held in disrepute because of its acids.
Old sawdust was marked safe, and fresh sawdust was set aside to age. To the writer’s knowledge, there has been one case where sawdust killed everything it touched. The man who used it said it was walnut sawdust.
No satisfactory explanation was found, nor was it possible to determine whether the sawdust had come in contact with waste products or chemicals harmful to plant life before it was used as mulch.
Many studies concur that sawdust from hardwoods, sawdust from softwoods, old sawdust, and sawdust that is fresh are all good mulches.
More details about the use of sawdust as mulch may be found in a bulletin. This bulletin, Sawdust As A Mulch, may be had free of charge by writing to the Agriculture Extension Service at Virginia Polytechnic Institute, Blacksburg, Va.
44659 by Martha Eckel