I put some Black currants and chilean guava in the ground last year (FYI chilean guava roots super easy) and the currants produced fruit but started looking rough in summer. The chilean guava has been cold protected on every 20F night but it still looks like a total “to ground” dieback if it comes back at all.
I was considering getting some loquat, serviceberry, honeyberry, feijoa, and other fruits that are touted as being hardy to 7b, but now I’m a little gunshy.
Is there a better way than hardiness and digging through historical archives of successes on fruit forums to find out the sustained cold and high temperatures tolerated by plants?
The whole digging a trench, cutting half the roots, then burying method is pretty tiresome when you’re performing it on several plants a year.
I guess some sort of database with notes like “This plant was successfully grown in X location with no protection provided. but failed y miles north or south.”
I don’t know if there’s any such database, but there’s a lot more to hardiness than zone, especially for fruit production. For example, my understanding is that loquat flowers and fruits over the winter, so it’s unlikely to fruit successfully even if the tree itself is hardy. Also, consider how hot it gets in the summer. Are you an inland Virginia Zone 7, a coastal NY/New England 7, great plains, west coast? These will all have very different summer and winter condtions. If your currants didn’t look so hot, they might need more shade and/or water where you are. Also, temperature conditions vary a lot locally. You might have very different conditions a mile down the road that deviate from the regional average, or on the south vs north sides of your house. The hardiness zone maps are a good starting point, but they are an estimate and can only provide so much detail.
As far as hardiness ratings for plants, they’re variety dependent and usually a nursery’s best guess of where something will probably make it long term, rather than determined through rigorous testing. Nurseries that are more interested in customer success will likely err on the side of caution, and those more interested in a quick sale may be a little more generous.
These are great questions to ask, but I don’t think you’ll find a centralized look up tool. Keep asking questions, learn as much as you can about your site and each plant you want to try, then decide if it’s worth the risk to you. You’ll get to be the pioneer and tell all of us what worked and what didn’t.
Yeah, the currants were in full sun so I moved them to mostly shade and they recovered a bit. 7b North AL which has meant wet winters with lows rarely hitting the teens, and summers with a month of two of sustained lack of rain and heat into the mid 100s every so often. If you can think of any non grocery store fruits that could fit that mold let me know!
So far we have 6 varieties of persimmons, one mandarin tree (gets covered with hay everytime the temp goes to 20), three fig varieties, two pawpaw varieties, arapaho blackberries, red raspberries, yellow raspberries, 5 varieties of blueberries, black currants, muscadines(volunteer), golden kiwis, hardy kiwis, spicebush, and pomegranates in ground for fruit.
please keep us apprised of how your Chilean guavas do.
i’m in a nice zone 6b and I’ve been tempted to drop one of mine in the ground and see how it does with a rose-cone or the equivalent covering it for the winter.
My biggest problem with these is that I see to always lose one over the winter indoors and start the next season with only 1 and then a need to propagate it rather than see if it will fruit for me.
I rooted cuttings of my chilean guava and mandarin tree just in case they didn’t survive the winter. I had one chilean guava buried below the soil line that naturally had its depression filled with fallen leaves on top and it still seems to be alive outside. The others are all quite dead looking for an evergreen. The plants are as close as plants can be to my hot tub and nearly fully protected from wind, so 6b is probably going to be very difficult.
yeah, but I have a pretty special 6b…(less than 1/2 mile from a lake visible from space)
My winter last year was a zone 8… this year we’ve not yet seen 0 (though I should have never committed that to print).
Mandarin tree? Che? Mine took years to fruit, but it was covered this past fall. (its also 15+ feet tall and has rarely suffered dieback of even branch tips…not at all in the last 5+ years)
If I could get a Chilean guava 3 years old and still have a reliable back-up I’d try it in the ground… There’s a variety called Ka-Bluey (and no its not TyTy…lol) that is supposedly a little hardier that I’d love to source, but I’ve only seen it available in the UK and not recently.
I think the zones are about to push back for the middle part of the country. jcguarneri is correct on loquats. They flower in the fall or early winter and must carry that fruit until spring. If it gets below 28 degrees the fruit will freeze and fall off. This year even in zone 9 they will not make it with the weather that is coming. Forecast for 20 degrees or below. Little fruits does not stand a chance. But the trees will be just fine.
Whoops, clementine orange (not Mandarin). In it’s first full winter outside (had a half winter outside last year). It’s on the NW corner of my house in full sun. I don’t remember the variety as it was a gift from my brother.
Having previously killed a gifted potted 40 year old grapefruit my wife and I decided it was going to live outside or die outside.
I guess a better first post would have been: What are you growing outdoors in 7b that would surprise people? A cold favoring fruit like currants in zone 8 or citrus tree in zone 6 would be examples.
Also, has anyone ever seen tayberries available in the US?
I have been zone pushing on a lot of fruits. What I have found is that it was not really about the plant surviving, it was that it never fruited. It either fruited to late in the season or flowered so early that frost killed it every year. When zone pushing look for early fruiting and late flowering.
Hardiness zone is just a measure of minimum temperature. Nothing more. Summer heat has nothing to do with it.
I found this during a search, and found it very useful. Just a sample.
Are the white currants good? I saw on Whitman’s farm the very unappealing description “probably the best tasting white currant, which isn’t saying much.”
I just spent awhile trying to find any concrete answer and I think the answer is no one knows for sure, so maybe someone on here with personal experience can answer. This was the closest I’ve found, which says: “At present, no information is available regarding the susceptibility of Rubus hybrids eg Tayberry and Loganberry.”
Lol, tell that to Texas which is about to have a cold front 2 zones below their normal winter minimums. I wouldn’t count on zone 6b to be 8 long term. But you know that
They are great. They taste like vitamin c citrus, sweet green grape, and a touch of yellow raspberry. They are tangy-sweet, and people who like sour candy should like them. I can confirm that the leaves will burn in sunlight when it is in the 80s. When other trees grow out, they will have late afternoon shade.
I would still try honeyberry. Maybe with a some afternoon shade. It gave me a bunch of fruit in 7A last year in their first year in the gound. Later in the summer it will get ugly and drop leaves but it might still produce well.
I planted the Dr Maxine Thompson varieties (Maxie, Solo, Keiko) and the University of Saskatchewan varieties (Beauty, Beast) on the recommendation of the nursery. They are supposedly more hardy in our humid climate because of their Japanese genetics.
