This section is from the book "Commercial Gardening Vol2", by John Weathers (the Editor). Also available from Amazon: Commercial Gardening, A Practical & Scientific Treatise For Market Gardeners.
When planting is completed place the boxes on a level bed of ashes and give a thorough soaking of water, repeating the operation till the soil is completely saturated with moisture. Daffodils of the class one has in mind delight in root moisture, and at this stage there should be no lack of it. Finally, twenty-four hours later, the boxes may be covered with fine coal ash to a depth of 6 in., an essential in the case to prevent lifting. Under this covering the bulbs will be safe for the coming-six or eight weeks, requiring no attention meanwhile.