Good Grapes for Less than Ideal Climate: Jupiter

Good Grapes for Less than Ideal Climate: Jupiter

Coastal Southern California, sunset zone 22, is generally not considered an ideal grape growing climate.  Nevertheless, we have had great success with a few grape varieties over the last decade and a half.  Between my friend across the street and I, we have grown Black Monuka, Fantasy, Glendora, Niabell, Eastern Concord, Canadice, Flame, Perlette, Interlaken, Einset, Marquis, Neptune, NY47616, and Jupiter.  More than once during a shift at the CRFG booth at the Green Scene I get asked to recommend what is the best grape for our climate, and always start with Jupiter.

cool coastal climate grape variety
The first Jupiter grape vine that I planted over the arbored gate to the vegetable garden.

We don’t get a whole lot of annual heat or even a lot of sun during June and July.  LIving not far from the coast, our summers are dominated by what SoCal locals call “June Gloom” for a large part of the early summer, with overcast skies until early afternoon, if the sun bothers to come out at all.  We also have higher humidity than communities further inland. Because of the mild weather, we are blessed to not need an air conditioner, but that also means successfully growing heat-loving popular table grapes found in the grocery stores, which is completely out of the question, especially growing them organically.

About five years ago, I planted, on the recommendation of a member of California Rare Fruit Growers, to try Jupiter, a purple, seedless, semi-crisp grape.  It produced a light crop after only 1 1/2 years in the ground, and I liked it so much, I planted a second one that same winter.  Jupiter Grapes are ripe when they are a dark purple on the skin and green inside, with a crisp sweet taste.  As far as my grapes go, Jupiter is the Goldielocks of grapes in the backyard.  It is not too small, not too sweet, not to tart, it is just right.

So far, we have not had any diseases issues on the Jupiter variety, including no powdery mildew, which often plagued my flame seedless most summers.  The humid conditions here aggravate the powdery mildew issues. Last summer we had very little sunshine, and it performed fabulously.   It is a moderately vigorous grower, which is much appreciated by the chickens who get many of the branch trimmings if the vines start to get out of control.  The Jupiter grapevine is a hybrid of American and European grapes, developed and patented by the University of Arkansas in 1998.

Jupiter is normally the second grape variety to ripen at my house, just a few days to a week or two behind Canadice. This year we picked our first few clusters on July 1st.  Most of the Jupiter grapes should be ready within the next few weeks.  Right now, some berries are still reddish.  I am aware that other parts of the country don’t start picking these until much later in the summer, but I would consider it an “Early midseason” variety of grape.

another jupiter grape cluster, what is the best grapevine
My other Jupiter grape vine is between the driveway and the backyard. It gets partial shade in the afternoon from the tree.

My second Jupiter grape vine isn’t planted in the best location and only gets half-day sun, at the very best.  Never the less, it still flowers and produces just fine, just slightly later than the one near the veggie garden.  It actually works out well for us, helping to stretch out our harvest.  If I had to pick one seedless table grape variety for coastal Southern California or similar cool climate, I would have to say Jupiter is the best grape.

Update: Since posting this, I have a newer grape that I like the flavor of even more, Petite Jewell. One of my favorite resources on growing grapes is book by Lon Rombaugh called the Grape Grower. He started a blog and maintained a website where he sold grape cuttings..

Jupiter Grapes in SoCal garden, one of the best grape for maritime climates, not just the South East U.S.
Jupiter grapes almost ready to harvest. The ruby red colored grapes are a little sour and the sugars are not fully developed until they finally turn purple
best coastal climate grape for powdery mildew
A cluster of the Jupiter Grapes, the one with the larger berries and purplish, next to a cluster of Canadice Grapes, the smaller red berries. The quarter is in the photo for scale.

8 thoughts on “Good Grapes for Less than Ideal Climate: Jupiter

    1. Second behind Jupiter? If I can only rate the ones I have tasted and grown here in zone 22…Overall, not just for flavor is Canadice. Its an excellent grape. It is sweet before being fully colored up and holds well for weeks and weeks, a little spicy, very sweet, super productive for a modest size vine, makes great raisens too. Its really early. I am already picking a few here. We are about 3 weeks earlier than last year. But if you want a cast iron no worries grape, eastern concord would be a really close contender for second place. At my house, it probably gets watered only once every 3 weeks or so in summer, only gets maybe 3 hours of full sun, has never had dieaese, and is very productive.

      If we are just talking flavor rankings, I still haven’t tasted 4 of my newer varieties: Neptune, Gratitude, Sweet Seduction, and Einset, so i can’t rank those. Out of the varieties grown at my house or at my neighbors that I have tasted, I think I would rank in this order: Jupiter, Fantasy, Black Monukka, Interlaken, Flame, Canadice, Glenora, Eastern concord (has seeds, used for juice & jam favorite,) Niabell (seeds,) Perlette. If productivity, disease, and mildew were no issue and I had unlimited space, I would happily grow all of them except Perlette.
      If you told me I could only have two grape vines, it would be Jupiter and Canadice. But I am looking forward to trying my newer varieties that have yet to produce, especially Gratitude and Sweet Seduction grapes.

      1. thanks you Lianne sincerely for the insight. I am in sunset zone 24, north of LAX, near your zone. My backyard faces south, however not all my backyard spots are 6 to 8 hours or more of sun. Plus as you stated in your article, we get many overcast days in the summer. I have a 16 x 16 x 8 pergola i just constructed and i got jupiter and himrod to cover. I bought the himrod before doing some research and now realizing it may not be a good fit in my zone. I chose himrod because it is a vigorous grower and favored by many. Need something that grows fast to cover my big pergola, yet robust and resilient to handle disease and lack of sun/heat. Jupiter seems to work for me. I will look into canadice or seedless concord as well, but i really want a green seedless to go with my jupiter…thanks again and good luck

        1. My Interlaken grape is from the same cross as Himrod, from Ontario and Thompson seedless. I bet they taste similar. Interlaken is delicious, with a hint of honey flavor and does well for me near the coast. It is my earliest grape so far. The majority of the clusters are almost ripe already. My neighbor planted the third variety, Lakemont, from the same cross. Give the Himrod a chance. If you don’t like it, you could graft over it with another variety later on.

    1. I never noticed this comment. I am sorry. I know it is way too late to reply, but for anyone else reading the comments, I got the Jupiter Grape from CRFG. They typically have a couple for sale at the Fullerton Arboretum Green Scene CRFG booth each April. Also, the variety shows up at a lot of the scion exchanges in January and February. I also have some propagated this year and available since Green Scene got cancelled. If you are local, send me an email. I might still have one or two as you are reading this. However, I do not ship plants.

  1. Oh, that must be frustrating! Do you happen to know what kind is it?

    Shade could definitely be a factor in your lack of grapes. Most grapes need at least 4 to 6 hours of sunshine, and full sun is considered ideal. My Black Monuka only produced lightly, and I figured it didn’t like the spot it was in. It got about half day sun, and we only got about 4 or 5 clusters each year, despite the rampant growth it always put on. When the neighbor extended the block wall and encroached on the grape’s spot, it was going to get even less sun, so I ripped it out last year. However, my Easter Concord gets only 4 or 5 hours, at best, and it gets tons and tons of grapes. It is planted on the West side of my house.

I would love to know what you think about this.

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