I just ran across this discussion, I too believed hollies were locked either male or female. Several years ago (probably about 10 or more years ago) I noticed a voluntary holly seeding that caught my eye because of it's dark and glossy leaves. It was growing in a bad spot, as it came up on the north side of a big planting of white pines and never got any sun at all. after several years at bloom time I checked on it and was unhappy to learn it was male. Who wants a male holly except for a pollinator. Well anyway the following year I was in the area at about bloom time so I went by to check on it and it had both male and female flowers!. I started asking around my nurseryman friends if they had ever heard of a holly that was monoecious. The next year when I checked it at bloom time it was all female. It has remained female for a number of years now with the heaviest berry set I have ever seen. following this by a few years I spotted another holly seedling that looked promising. It was only about a foot tall but looked to have been heavily sheared and very pyramidal. when it reached flowering age it too was male (and still is) with the heaviest flowering I have ever seen. It grew very slowly until it reached about 3 ft wide by 5 feet high. I thought even though it is male there is a place for it as a specimen plant. However the following year suddenly it about doubled in size going to about 6 ft by 10 ft. So then I wondered if it would not be a great screen plant. Since then, at least 6 or more years it has grown only a few inches taller while getting wider and a bit more rounded. A couple of nurseries are trying it out. one as field and container grown and the other has just rooted cuttings I gave them. The purpose of all this talk on the second plant is I some years ago rooted about 90 cuttings. I planted a row of them on my property and when they got to blooming size the first one in the row had female flowers. but then seemed to revert back to male. Later I planted another row of eight at another place. after they started to bloom they were of course male. Then a few years later when I checked them seven of the eight had female bloom and the set berries. The following year there was a late freeze and killed the bloom so no berries. Still remains to be seen if they remain female. The purpose of this long article is to say hollies do sometime change sex. At least they have at my place. BTW I am a North Carolina Certified Plant Professional having been the nursery business for most of my life and now at the age of 85 and still growing Sempervivums (More than a hundred varieties) and wholesaling them to local garden centers and nurseries.
