I don't suppose they gave any reason for that. I hate when people do that.

The only thing I can *possibly* imagine is that it would offer too much nitrogen. I know bulbs need some phosphorus to get nice fat bulbs. But if your soil is that sandy I can't imagine it would hurt anything and it will provide P as well as N. I say pile it on, or if you just can't stand not knowing, ask them to explain themselves. 50/50 says they can't.

I assme Van Englemen is a nursery you deal with. Did you bother asking the nurseryman who told you not to do the manure thing why it should not be used.

I think maybe, you gave him thought you wanted to use the manure as a planting aid...by putting the manure directly under the bulb. We don't put fertilizer there also, nor do we put the bulbs in direct contact with phosphurus enriched chemical which can burn the tender roots that form.
Any booster (phosphurus) is well mixed with the soil that is under the bulb, then watered in well.

Instead of the manure, try giving your planting hole some superphosphate or triple superphosphate, or bone meal.
(if you don't know the terms, then do your own research on them. Superphosphate has an elemental 0/20/0....and triple superphosphate has an elemental 0/46/0....so you can see the increase phosphurus level these have.
They are commonly used in this manner....as well as a help whenever we plant and transplant. Roses would be lost without the help of these.

For a mulch after the bulbs are planted, use your well-composted manure to help the surface soil retain moisture and keeps up for added time the soil temperature.

The roots of spring flowering bulbs are dependent on the soil temperature being less than 50º in order to form and once formed will protect the bulb from whatever winter throws at it.

Defining terms may be of importance here.
Straight cow manure will have higher N than composted, but IMO, N isn't high to start with, though fresh may "burn" the bulbs.
"Well composted" would indicate material with very low N content but excellent organic matter to incororate.

Composted manure is around 1-1-1 I think, if not lower.

I believe this really was a matter of concern that the manure would be too hot. This manure is quite aged, though, and I don't really think that will be a problem. I have wanted to hear from others, though, if this was something I should really fret about before planting some 300 bulbs at a new house. I think I'll mix in some peat, too. Any other thoughts are welcome. Thanks to those who have responded. All useful. Love gardenweb.

If you read the planting instructions at the Van Engelen website, it says very clearly: "Never add horse manure, mushroom compost or other "hot" manure or compost to your flower bulb beds." The key word here is "hot" manure or compost, meaning the manure should be fully composted before application and the compost sufficiently finished and aged. It is very easy to 'burn' or damage bulb roots, which start developing virtually from the moment they are planted, if the compost/manure is not properly aged and comes in direct contact with the roots.

And having said that, it is never a good idea to add compost directly to a planting hole -- it is far better to amend the entire area to be planted rather than individual holes. This will help with moisture retention but still allow for the very fast drainage bulbs require. FWIW, I probably wouldn't bother amending at all. Most spring flowering bulbs are native to areas that have very lean, even rocky soils and experience prolonged dry periods, especially in summer. Duplicating those growing conditions will provide a pretty near ideal planting situation. And NO peat! It adds nothing, may be too moisture retentive and will acidify the soil unnecessarily.....bulbs prefer a close to neutral pH.

Also apply bulb fertilizer, if used, only to the soil surface - again, do not include in the planting hole either. FWIW, I've never used bulb fertilizer in my life and somehow have managed to grow wonderful spring flowering bulbs that have naturalized and return year after year. Also have managed to grow roses quite well without the help of any bone meal or triple phosphate :-) I just mulch annually with compost and supplemental fertilizing of pretty much anything is unnecessary.

You speak wisely, gardengal. I find the soil appalling. So I might just mix in a very slight amount. Or not. Rhodos were doing fine there. So there must be something in the soil.
Thanks for your thoughts.

Skip the peat ... if it dries out, it's almost impossible to moisten again.

Well-composted cow poop is not going to damage the bulbs.

Gardengal has some very good advice on bulb planting. What the Van Engelen people tell you is very much like what you would find at the International Flower Bulb Centers web site, "This is the web site of the U.S. Netherlands Flower Bulb Information Center, the press information office of the Dutch flower bulb industry."
some 30 to 50 years ago it was common to suggest adding phosphorus to the planting hole of many things but about 25 years ago horticulturists started seeing many problems with that and stopped recommending doing so, and today we know that excess phosphorus in soils will migrate to water and creat major problems there.

Here is a link that might be useful: IFBC