One example of cheap Epsom salt HERE .

I can send you if you wish a strong Miticide in a envelope. You can find it at every garden shop here. If you wish that just give me a message. It will cost maximum 2-3 Euro.

I can send you if you want grapefruit or other citrus bud-wood if you know how to graft.

I keep some of my citrus in central heating conditions (the ones in the pictures are just above a heater) but the humidity level is always more than 60%. If it goes lower I mist them but that will happen once every week. The water in the tray does its job. Combined with the Miticide the mites won't appear for months.

The plants will do just fine. If you can go higher with the temperature will be better but then you will have other problems if you don't have enough light.

Hi Covrig, Just PM'ed you.

I have to consider ordering that Epsom stuff. Maybe I'll make a visit to local pharmacy first, since the postage costs from another country for a kilogram packet might be high (edit: actually they seem to ask only £3.50 for the postage - incredibly cheap!?). Any idea about the dosage?

Light is actually cheaper than heat, so maybe I'll bring the plants inside later and give some extra light. However, it's only less than a month to the shortest day of the year, after that the days are already growing longer and every day more daylight is available... keeping the plants more or less dormant over the darkest months is a very cost-effective way, but the downside is the short growing period.

I made an order now from Ebay. At least the magnesium part is now in control for some time.

Looking at your grapefruit, I don't see symptoms of a magnesium deficiency. The symptom for magnesium deficiency shows up on the OLDER leaves, with the lower center portion of the leaf blade showing a green delta shape, with the leaf tips and sides remaining yellow. In normal citrus container cultivation, if the fertilizer used does not contain magnesium, Epsom Slats should be added 3 or 4 times a year. However, to answer your question concerning the use rate for Epsom Salts (Magnesium Sulfate), dissolve one tablespoon in a gallon of HOT water, and apply the cooled solution to the tree's root system. If a magnesium deficiency is being corrected, repeat once a week until deficiency disappears. NOTE: Always dissolve Epsom Salts in hot water as it does not dissolve well in cold water. - Millet (1,143-)

Ok thanks Millet, I will give it some Epsom salts anyway when the stuff arrives, since so far I have not found any fertilizer containing magnesium. Maybe some specific Citrus feeds have it, but such a thing is unknown here. I guess there must be some in the soil to start with, but the plants use it in time. The picture is bad, all the leaves are more or less yellow. I guess some magnesium won't do any harm, even if there is no deficiency yet.

I removed the dead, dry leaves now and that made the plants already look more alive than before.

My nine-months-old lemon seedling is a strange case, it looks just fine and is growing like nothing, and it has been inside on a windowsill for the whole summer - no spider mites or anything. Maybe lemon doesn't taste good to the little devils. Changed the pot today, since the roots were already more outside than inside the old one. It's already taller than my lot older clementine and trifoliate plants.

Thanks for everyone for the advices, I'll get back to this and tell you what happened to the plants later.

Jari

Ps. It has been raining for several weeks now, looks like the winter never comes. But the good thing is, that the air humidity stays up in this weather, just checked the meter in kitchen and it says 79% which is quite high and good fo the house plants. When the real winter comes, it will drop to 30% or even under 10% in worst case. I think I should have an air humidifier, or at least an aquarium...

My grapefruits have now been inside for some time, and already there is tiny new growth on them! So I think the plants will really survive. I haven't given the miticide yet, since I can't see any trace of mites, but it's good to have the stuff available since the dry indoor air, especially in winter, is much too welcoming for the spider mites.

Actually, I consider mites to be one of the easiest pests to eradicate, by spraying a horticultural oil such as UltraFine (sold at most garden centers, and Home Depot). - Millet (1,112-)

Never heard of such oil. Things may be a bit different here than elsewhere, Finnish gardening and house plant culture is not very sophisticated and you might be suprised to see how poor selection of plant care chemicals is available. It's not only a bad thing though, since some of them are quite poisonous...

But we use liquid pine soap or pine-Tolu (cleaning agent, which apparently contains some sort of soap and isopropanol, name comes from toluene which it used to contain but not anymore) mixed with water and sprayed on plants, especially the undersides of leaves. Normal spray-pesticides like pyretrine also work somehow, but the problem is that they only kill the adult bugs.

Outdoors the mites are never (or very seldom) a problem here, I guess if it's not because of the climate or humidity, maybe it's the predators. Indoors they get to some plants, mostly Citrus and Capsicum.

I use Ultrafine on mites quite often. Works like a charm.

Ah, Epsom Salt.. quite it's in every gardan store available... it's magnesium sulphate, so called epsomite or bitter salt.
Usually recommended for conifers, but usually also good for Citrus.

I can see that there is a product called "Neem-oil" available in some finnish gardening web-stores. Would that work? It's organic...

Neem Oil can also be used, but the odor is terrible, and it does not work nearly as well as UltraFine. If your worried about whether a product is organic or not, then don't worry about horticulture oils. UltraFine is 100 percent non toxic, and 100 percent safe to humans and animals. It is not a poison it is an oil. I am not an organic grower, but I believe horticulture oils are approved in organic culture. Just about any insect problem your tree will experience, UltraFine will probably take care of it. It works by smothering the insect, NOT by poisoning it. Never ever spray a citrus tree with anything during the heat of the day. Spray either very early in the morning, or at dusk. Good luck. - Millet (1,108-)

Thanks. Everything doesn't necessarily have to be organic, but it's always positive sign. I don't think I can buy Ultrafine here, but maybe something similar, I'll keep my eyes open for it. Meanwhile I have the poisons sent by Covrig and the pine-soap solution.

The main Problem is, that most Oils are not labled in Europe as in USA.

So in europe oils sprays are recommended as spring flush sprays. That are the oils one has to seek in Europe, to get what here is recommend as UltraFine.

Usually here one will find typical products,
like Promanal from Neudorff or Natria from Bayer Chemicals.

Promanal is made of plant oils, rape oil is used here
The Bayer Product uses common mineral oils...

That may help