If you have any personal experiences related to certain species or varieties you would like to share (along with your location), such as average bloom dates (preferably between 50% and 90% open, but dates paired with any flowering stage can be useful), ripening dates, disease resistance, etc..., or if you spot a potential inaccuracy on my website, let me know, and I'll take it into consideration.   The more detail you supply, the better, but basic information can be very useful too.
You can reach me at
(enable javascript)

v5 pages have undergone considerable updates to their species and variety section, although they will likely receive many small or moderate updates in the future.   v4 pages still need a large update to their species section, but the variety section is in fairly good shape.   v1 pages are still on their first version and are in great need of a large update to both the species and the variety section.   Some of them have been delisted from the menu, but the pages are still live.   v2 and, to some extent, v3 are similar to v1, but they are in better shape.

v5: chestnut, *juneberry, persimmon
v4: *almond, apple, *apricot, blackberry, jujube, mulberry, pawpaw, peach, pear, plum, pomegranate
v3: *gooseberry, **honeyberry, *kiwi
v2: cherry, hazelnut, strawberry
v1: *currant, **cloudberry, **medlar, **melonberry, nectarine, **prickly pear, *raisin tree

*reliable information is more difficult to come by than usual.
**reliable information is very hard to come by, so the pages may always be quite bare.

Chill Hours

Some plant species, particularly ones native to the temperate latitudes, require a certain amount of chill hours to prepare for the next grow season.   Chilling can be received between the temperatures of 32F to 55F, but it is most efficient somewhere between 35F to 50F.   Additionally, temperatures above 60F can reduce accumulated chill hours, to some extent.   The most common chill hour map, however, is strictly based on temperatures between 32F and 45F.   With the exception of Mediterranean climates, since they typically receive significantly more chilling hours than what is displayed, it is accurate enough to give you an idea of what to expect, but an improved version based on the Dynamic Model may become accessible to the average homegrower at some point.  

Varieties that are said to require 800 chill hours don't exactly need 800 or more to fruit.   One study found that you can still grow a decent crop after receiving about 50 to 100 chill hours less than the recommended amount.   Below that will not only reduce crop set, it will also reduce fruit quality as well as delay bloom, reduce pollen production, and discourage a healthy leaf set.   Receiving 300+ chill hours less than the recommended amount may completely prevent the tree from setting fruit and even cause some dieback.  

Planting varieties that require a much lower number of chilling hours than your area generally receives may not be a good decision for some.   Climates with large, frequent temperature swings during the winter or early spring often prevent them from fruiting (this is a problem throughout most of the US).   Not only are their chilling requirements satisfied early in the year, but the amount of heat units (grow degree units) required to bloom are easily accumulated as well.   This dramatically increases the possibility of an early bloom which exposes the blossoms to a greater chance of experiencing frost damage.

Additional Comments

You are better off assuming "self-fertile" plants are "partially self-fertile" because having a pollinator usually increases yield, sometimes dramatically.   In some cases, you may prefer to not have a pollinator.   For example, some species, such as Asian Persimmons, produce seedless fruit when pollen is absent (parthenocarpy).

If you see something like (hardiness) "Zone: 5 (4)" on the site, it means it's probably hardy down to zone 5, but if it's not, it's more likely to be hardy down to zone 4 rather than a zone higher than 5.   Alternatively, "Zone 4 (5)" means there may be a little more evidence that it's hardy down to zone 4, but if you want to play it safe, you're better off getting it only if you're located in zone 5 or higher.   I also want it to be more visible to people who search for varieties based on "Zone 4" because it's a good variety to experiment with, for those who are up to it.

When referring to the cold hardiness of a species as a whole, something like 5a/6/4b may be used.   5a/6/4b means that the majority of the varieties from this species appear to be hardy down to zone 5a, but some are as high as zone 6, and others are as low as zone 4b.   Sometimes the hardiness of a species doesn't have as much variation, so I may use something like 5a/6 or 5a/4b, with the first one, again, being the most common among (the most widely sold or newly developed) named cultivars.