Hello, This is my first post, I have a question about watering newly planted grapes in this Western Arizona Hell Hole. I planted my grapes in February, they were doing great until the Temps in this area started hitting 110+. Is it possible to over water grapes in this extreme heat? This week we had temps around 120 and the grape plant seems to be frying. I water daily just at dark with a bubbler system for 10 minutes. I had a Ruby Red that completely collapsed and died seemingly over night, and now the Thompson's I have left is showing brown spots on the edges of all the leaves, and some have brown spots in the center of the leaves.
Could it be a tad warm for them??? :) Also we have been advised to water early morning during our drought. Apparently plants make better use of water. Is the root area mulched to keep them cool. Maybe you have fried roots. Can't stress mulching enough for the type of weather you seem to have. "The ideal temperature range is between 18 and 32 degrees Celsius" 32 is definatley lower than 100F. which I think is about 36C or 38 C May also need artifical shade on bad days. Like people do here for Hortensia (Hyderangea) or for frost prone areas they cover lemon trees Liz
This weather is pretty much, par for the course in this area. We have about 60 more days of 110+ yet to get through. I'm trying as hard as I can to get them through thier first summer.
Maybe your Hell Hole lies outside the tolerance range for grapes. Are there any vineyards or other plantings around?
Yes, about 1/2 mile away some folks have a HUGE Thompson's plant. It gives more grapes in the spring than 3 families could eat. It is however located about 40 yards from the Colorado River bank. I can't ever catch the owners at home to ask how much they water the thing. I can see 3 bubbler heads within 5 feet of the main trunk( yes trunk, its bigger around than 90% of the "trees" here.) Also 12 miles south of me is a 5-6 acre vineyard, it is in an agricultural area and is irrigated. That area is MUCH cooler, due to farming, about 20,000 acres of alfalfa, and assorted vegetables.
I live in Phoenix, another hell hole. I've had Thompson seedless grapes for about 15 years now (the same plants). The leaves tend to wither about now but the plants do quite well. I water in the morning, and put the grape clusters in brown paper bags to keep the birds away. The leaves will all fall off in another month but the plant is fine. Terris
Terris, How often should I water? That is the main question here. We are only a couple hours away from each other and our temps are only about 3-5 degrees warmer. I did mix some mulch and potting mix in with the "native" sandy soil. The holes I dug were about the size of a 5 gallon bucket. The plant has two 4' vines right now.
That probably made them more apt to dry out, actually. In future do not amend planting hole backfill. You want the same soil throughout the entire rooting area.
I only water about 15 minutes in the morning. I also don't mulch the area around the base, only fertalize in the spring. I get a lot of whiteflies but the grapes are all in bags so they are protected. Terris
I know wine grapes respond favorably to dry conditions. I spend a lot of time in Richland, Washington (major wine grape region) and the vineyards here are given just enough water to survive. Summer temps here have been in the 90-105 range just about every day this summer and the grapes here THRIVE. I realize its quite a bit hotter than 90-105 F in much of Arizona, but my point is many wine grapes like a bit of heat. Hope this is at least a bit informative for you down in Arizona. Peace!
That's nice to hear. I live in Phoenix and I thought I really underwatered my grapes but they have always done well. Thanks for the info. Terris