I have 3 citrus fruit trees growing in large pots, 1meyer lemon,1blood Orange,1 ponderosa lemon. Last year they spent winter in small greenhouse, no fan, no heat but covered w blankets. They survived, barely. Blood orange n ponderosa lemon had booms. I tried to pollinate them w Qtip but destroyed blood orange blooms. Ponderosa is self pollinating n I have 3 huge lemons(3 blooms fell long ago). I need to know what can I do to ensure survival n fruit production for next year. I fertilize them w citrus fertilizer. The plants look very healthy but no oranges, no lemons. I'm planning on putting a fan to circulate air n small heater which I will shut off at night or when I'm not home. Any tips would be greatly appreciated. Thanks!

IMHO, shutting the heater off at night is not a good idea, I'm sure other members will give you some advice. to the forums, there are alot of knowledgeable people here

Like any tropical plant, the night temperature is the biggest danger for them. All my greenhouses are heated, not with one heater but with two and then I have a third heater that only comes on if the temperature dips below 50F. All my heaters have independent thermostats. I keep my greenhouses at a minimum of 55F.

I am not sure what Zone you are in. I am in Zone 9a. (rare snowfall) I keep my Improved Meyer Lemon, Satsuma Orange, and Meiwa Kumquat outside until there was threat of a freeze. Then they went under the porch. That is all the protection they got other than a good watering to keep the roots insulated. (Dry soil has no insulation). When there was threat of a hard freeze of more than 12 hours, they came into the house in front of a sunny window until the threat passed. There was some leaf loss but not enough to worry about.

They survived, and put on lots new growth and flowers unfortunately a bad spring storm knocked off most of the flowers on the lemon and orange. I have two or three large fruits on them right now. The kumquat however, flowered in 3 cycles and is loaded with fruit that will be enjoyed this winter as usual.

I am also in zone 9a and have quite a variety of citrus trees that live out all year around. They are now very large, but for the first year or two while they were getting established, I covered them whenever a freeze was expected. I suspect, as you are farther north and your citrus trees are potted, you will always have to offer yours greenhouse protection in the winter.

Unfortunately, true. I don't know what I am going to do with this fairly large tree and six rooted cuttings.

I would try to prevent dry-moist-dry soil episodes, fertilize as needed per label directions and definitely not let them get too cold in the winter months. I have to bring them inside the house when cold weather rears its ugly head. And in my house, I have to keep the pooches away when I apply the fertilizer as it appears to smell 'nice' to them.

I have to water this (fairly large) tree every single day. It will come in with all the other 1000 tropical plants next month. I am going to trim a couple of feet off of the main, vertical stem and a foot or so off of several of the side-branches. I won't trim the branches in flower though. Perhaps I will have fruit set during the fall and winter months.

We are in zone 9b so our citrus are all in ground except one lime in a pot. We always cover the potted one and covered the in ground ones when they were small and we were having below freezing temps. They can be amazingly resilient. We have also used Christmas lights to provide a little extra heat. Just a thought. Sounds like a nice collection!

Thanks, Mary. I would not call it "nice". A ton of work all year long but particularly in the fall and spring, when every one of the plants either have to go out or come in.

Lots of work indeed!

I keep telling myself: "Labor of love, labor of love, labor of love". Sometimes there is so much labor there's not room for much love.

I have had fruit set during winter on some years so good luck with your tree! I think I harvested mine finally around March-April.

Interesting! Some of our citrus starts getting ready to pick around Thanksgiving with most of it ripening between Xmas and the New Year.

Thank you all for giving me valuable tips about my citrus trees. I think my growing zone is 8 but lately winters have been very harsh, ice n snow n temps below 20*. My greenhouse is very small just enough for my 3 trees so I can't really put heaters n fans as I want. But I understand about leaving the heater on during the night since it gets colder then,but I don't want to start a fire if I leave heater on for many hours. That's why I cover them w/ blankets n then heat the area for short periods of time. By the way I trim my trees before I put them in greenhouse so they don't touch in case there may b white flies, which I did have last year. That was quite a job to get rid of! If anyone has more suggestions on how I can keep my trees healthy n growing in winter I thank you in advance. They're potted not in the ground.

Anrobes, you might want to invest in a greenhouse thermostat. These are very accurate, much more accurate than the built-in thermostats that you get with inexpensive, electric, space heaters. That way, the heater only comes on when your greenhouse gets down to a certain temperature and shuts off when the temperature is above that low setting. Many of those thermostat controlled heaters are junk, at least when it comes to accurate on/off functions. I run six heaters during the winter (several greenhouses) and have done so for many years. I have never had a fire. My heaters will shut off if they are tilted and they all are of course on breakers.

I know little about growing citrus, having only the single tree that overwintered in a greenhouse last year. I did not have any white flies. I guess IF I had a greenhouse dedicated to citrus and had a pest problem, I would use dormant oil spray on those trees. I am sure others will have experience in growing citrus and can advise you more than I.

Thank you, dr.dawg, I will get a heater w/ an automatic thermostat. I have used dormant oil before on all my fruit trees so I guess I will also use it on my citrus trees.
I have another question n may you or someone else can help. Last spring my ponderosa lemon n Meyer lemon bloomed, but they're in a lanai covered w/ a screen so I tried to pollinate them manually but the Meyer lemon lost all its booms,while the ponderosa lemon kept most of its booms n I do have 3 huge lemons that survived the very hot weather this year. My question is this: r some citrus plants self pollinating ? Is the ponderosa lemon one of them? Thank you!

I don't know. Someone else will have to help you with that question.

I have fall flowers on my Meyer Lemon. I hope they fruit for me. Only got 2 lemons this year. A spring storm knocked off all the spring flowers and little lemon starts. Oh, a note on the Christmas lights. (I love that idea btw) Make sure they are the old fashioned kind, not the LED type that give off no heat at all.

Yes, I think most citrus are self-pollinators. Here, where nearly every house has a citrus tree or two you often see a tree all by itself, but covered with fruit.

It really depends upon the variety of citrus, when they will set fruit and ripen. There are types of orange that ripen as early as October, and some that aren't ripe until March. At our first house here, I planted 3 different orange trees, so that I would have a continuous supply for juice from fall until spring. Then of course we moved away just when the orange trees were big enough to start bearing . . and the new house doesn't have enough space. (well, can't complain, I do have a very nice big mango tree here)

For your whiteflies in the greenhouse, a soapy water spray is probably more effective than dormant oil spray. 1/2tsp. of dish soap to a quart of water, spray all surfaces of the leaves and stems, at least twice about a week apart or so. Then spray every couple of weeks to keep the beasties from starting up again. If you have a warm day, pulling them out or taking the hose to them for a thorough shower inside the greenhouse also takes care of a lot of insect problems, and the plants will love the wash.