Hi Hobby exactly what Cory mentioned. I have my veggies in my GH and the alarm has been set off a few times so far we have the alarm set at 100 degrees. So far so good all my veggies are doing remarkably well . Another thought I do recall Evans temps in the desert get well over 112 degrees for quit a few day's in the summer and his trees are gorgeous probably not the best growing conditions but they survive . Lot's of ventilation is key Hobby .

Brian

Thanks Cory and Brian! Yes it is just a small greenhouse and the door is wide open so it gets lots of air. I have a thermometer on the ground so I can monitor root temps and I don't think it has climbed over 35 C or 95 F so seems ok. I will keep monitoring them as the temps climb. They seem to be loving it that;s for sure!

My truck said 118 outside on the way home from work today. Forecast says 121 tomorrow, 95 will be fine for your greenhouse just make sure you have plenty of ventilation like Brian said.

Evan

According to this article, the maximum temperature for citrus growth is 37 to 39 C (98.6 F to 102.2 F). http://www.crec.ifas.ufl.edu/academics/classes/HOS6545/pdf/mendel_1969.pdf

Root growth shuts down above 95 F.

Wow Evan that's crazy, and so dry too! Do you notice and growth stalling in those heat waves? Thanks for the comment.

Hi Vlad, thanks for the article I will be sure to watch the temps. When we get our hottest days here I could definitely creep into that range but the pots are small so I can easily bring them out. I also keep the pea gravel floor hosed down so I hope that helps keep it a bit cooler.

I hit 130F several times and had some wilting. Once the sun set the trees perked up. I toped 120F a little more often. and temps above 110 were numerous. Hy trees grew great. Other tropicals like peppers died.

6b Steve

Hobby,

Like Brian I set my alarm but at 95°F as that is when plant growth begins to shut down. When the alarm goes off it reminds me to go check the roots and feel the leaves to see if they are too warm to the touch and to check everything is ok or needs water, misting, or more ventilation. If you can keep the air moving in the greenhouse you will be fine. Some smaller greenhouses don't have enough vents to let the heat out even with the door open. You have pea gravel so if you just wet that down that will help to keep the temperature down and the humidity up and works well and costs practically nothing. Use fans to push the hot air out of the top and bring cool air in from the bottom. If you put up shadecloth it is more effective on the outside and raised a few inches above the glass/roof. The shadecloth reduces my inside temperature about 15°-20°F and so does the wet floor. Good luck. You just have to experiment and see what works for you. An alarm is worth the cost.

Cory

A lot of great advice and info from you guys.. Thank you, Hobby for starting this thread. I hope it helps you and that your plants all thrive whether inside the gh or outside. I am in the same boat as you weather wise..

We have had a number of heavy rain storms with strong winds at least three times a week since the middle of May. One of my ST lemons shook so bad from the wind that it uprooted a few of the feeder roots. Boo...I have been constantly shuffling my plants in and out of the greenhouse, to sunroom, to back out on the deck. Most of the plants started out with a good growth spurt, then despite fertilizing often the leaves just are not greening up like they should. All the rain flushes out the fertilizer..Hubby and I recently moved the biggest and oldest trees back out to the GH for a while. Possibly the rest of the summer. I will water them with rainwater collected from the rainbarrels.. I am going to keep the younger and smallest trees in my sunroom on the cold, rainy, windy days, then back out on the deck when it is nicer. Easier to shuffle the lighter pots in and out and my back does not suffer... lol

We have a cold front moving in along with more rain over the next few weeks. A low of forties in the evening, sheduled for next week.. sheesh..

Jinny, that's what I've been doing too, moving pots in and out of the sunroom ;-) It's been cool and wet and whichever plant I want to hurry along gets time inside. Even if it's cloudy they seem to grow when they're out of the wind and cooler temps. I think that's why my baby meiwa is blooming and the centennial kumquat is showing lots of new leaf growth with flower buds in almost all the clusters.

cf03, we do what we have to for our trees best interest don't we?.. Some of us have a short growing season and we need to do what works best for our citrus in the long run before we bring them back at the end of the season.. I recently aquired a young Centennial Variagated Kumquat also. It is basically a tall stick with a small canopy at the top. Lol. The nursery where I aquired it shaped it into a tall tree form.. It has no buds yet, but is leafing out a bit farther down the stem now, which I prefer.. Is yours bushy or in tree form?

Hey Hobby, we actually made it to 124 today according to my truck. All of the new growth was zapped pretty good today, not sure it will survive through this week. I went outside and took some photos to show what extreme heat damage looks like in citrus trees.

Pomona Sweet Lemon, notice the cupped and drooping leaves.

Citrus heat damage · More Info

Meyer lemon same symptoms

Citrus heat damage · More Info

Close up of damage on Meyer

Citrus heat damage · More Info

Eureka lemon damaged on new top growth

Citrus heat damage · More Info

Eureka damage

Citrus heat damage · More Info

Young Oro Blanco first year in ground

Citrus heat damage · More Info

Oro Blanco close up

Citrus heat damage · More Info

Evan

Jinny, my centennial kumquat is like a little tree. It's kind of lopsided right now but with all the new growth coming I hope it'll even out. It's also leafing out lower on t he stem so I'll have the option to let it get bushier.

Evan, I can't imagine living where it is that hot. We did hit 99°F a couple times the past few weeks which is high for here, especially in June. I hope your trees survive. You too! Thanks for the pictures.

Cory

Wow Evan that's really sad I have always been amazed with your tree's. I have all my fingers crossed for your tree's and hope the heat wave breaks. I was watching the forecast this evening and they mentioned that Las Vegas reached 45C I cannot imagine how hot that would feel . I believe your tree's went through something similar last summer but probably not as severe . Wishing you the best buddy

Brian

cf03, your little Centennial Kumquat is quite lovely. It definitely has more branches and growth than mine. :) I hope by the end of summer it will fill out more..

Wow, Evan. . Your poor, beautiful trees took a major hit with those temperatures. I hope they recoup soon.

Thanks Cory, Brian and Jinnylea for the well wishes and sympathy for our hellish temps lol. My trees actually didn't do that bad, they recovered for the most part over night but some of the freshest growth was damaged and probably won't recover. It was much nicer out today we were down to a tolerable 118 ha!

I had fresh shoots on my tangerine tree that went up and curled back at a 180 wilt/droop. The got better over night and then drooped the next day when it was hot. There was no long term damage at all.

6b Steve

Yikes Evan, well if it isn't one thing then it's another right??? I hope they recover nicely, they look gorgeous! How has your little potted tree from last season held up, I can't remember which one it was?