Hi Dawn, welcome to the amaryllis forum!

I am difinately not an expert but sounds like too acitic from pine needles or too wet from mulching. I've lost lot of my bulbs after I had continuios curving put in, wasn't draining out like it used to. I've mulched other plants with different type of mulch and it was keeping amies too wet.
I am sure some of the experts will chime in soon.
Good to see you here, great bunch of people here at this forum.
Good luck!

Jan

I don't grow my Hippeastrum bulbs outdoors in the garden, but my guess would be the mulch allowed for too much moisture to be retained, and if you dig them and take a look, you may be slowly losing them to rotted root systems... Hippeastrums require very good drainage and hate to remain too wet for too long. There could also be an issue with the acidity of the pine needles... this, I'm not sure about.

I would do a bit of investigating with a shovel... find out what's going on under the soil.

I plant amaryllis about 4" deep in sandy loam and mulch with shredded leaves over winter. When grown this way, they flower in June and early July. A few have disappeared, but most do well.
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