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Citrus trees in the greenhouse !


Ok, so what i know about citrus trees you could probably write on the back of a postage stamp ! I am told that one of these is an orange tree, two lemon trees and one is a lime tree. The lime tree is easy to recognise ;)

However, I am not sure about these three.

I think the one on the left is a lemon tree, have had it for about a month and the amount of top growth is certainly very encouraging, but the other two have been flowering profusely for about the last two weeks… Too many flowers though i think. Any advice would be gratefully appreciated. Havent really got a clue….

Yours truly TLG

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~hi there ~I think you have a Citrus mitus far left~(I have one which has mini oranges)~ second down~see if any of this from the RHS helps you~

Native of warm areas such as the Mediterranean, citrus can be grown in cooler climates provided they can be kept frost-free during winter. With increasingly milder winters and improved hardiness of new cultivars this may become unnecessary.

There is a range from which to choose: sweet oranges (Citrus sinensis), mandarins (C. reticulata), lemons (C. limon and C. x meyeri), limes (C. aurantiifolia), grapefruits (C. x paradisi), kumquats (Fortunella japonica), and calamondins (x Citrofortunella microcarpa).

Their fragrant, creamy-white flowers appear on one-year-old shoots in late winter, and the fruit ripens nine to 12 months later. Because their fruits take so long to mature they are often in flower and fruit at the same time.
Site and soil

Position citrus plants in as sunny a spot as possible, especially in a cool climate, as it’s essential they receive sufficient sunlight to ripen.

While some species are more cold tolerant, none is fully hardy and so benefit from being brought into a frost-free place for winter.

Despite often being marketed as such, citrus generally don’t make good houseplants where there is a dry atmosphere caused by central heating.
Buying and planting

Most citrus (except grapefruits) attain a height of only 1–1.5m (3–5ft) when grown in a pot. All types are self-fertile, so only one plant is needed to set a crop of fruit.

When buying, select a plant that has a balanced framework of branches and a strong graft union; it can take citrus scions a few years to graft strongly to their rootstock.

In a cool climate it is usually best to grow them in pots, so they can be moved around to make the most of warmth and frost protection. For this, use a loam-based compost such as John Innes No 3.
Plant care

Citrus are hungry plants and respond well to regular feeding. Most of the flowering and fruit ripening occurs in winter, when they need a balanced fertiliser; summer is a period of leaf growth so a high nitrogen fertiliser is preferred. Specialist citrus feeds for spring/summer and autumn/winter are available and worth using.

Keep citrus plants well watered except during winter, when the compost should be allowed to dry out slightly between watering.

To ensure adequate pollination keep the atmosphere humid in winter when plants are in flower – hand mist regularly, stand plants on trays of moist gravel and group plants together.

Pot up plants annually in early spring, or top-dress with fresh compost.
Training & pruning

Because citrus are usually bought as established plants, often no formative pruning is needed. However, regular pruning is needed to maintain the shape of citrus trees trained as standards, with a clear single stem and a rounded canopy.

When pruning, take care to avoid vicious thorns that many citrus bear.

The main pruning period is late winter, just before plants come into growth.

If too many fruits are produced they may need to be thinned out – a plant 1m (3ft) tall should bear no more than 20 fruits. Kumquats, however, don’t need thinning.

Recommended cultivars
Orange, calamondin and mandarin

All bear spherical, orange fruits. While sweet oranges and mandarins are tolerant of temperatures down to 7°C (45°F), calamondins need a temperature of at least 13°C (55°F).
‘Washington’ (sweet orange)

This sweet orange cultivar is widely grown commercially, and its large, seedless fruits have an extremely good flavour and high juice content. The trees are vigorous and fruit ripens in late autumn.
‘Tiger’ (calamondin)

The leaves of this cultivar have variegated stripes, hence the name. Bears masses of orange fruits, 4cm (1.5in) wide, on vigorous plants, which are best pinch pruned regularly to keep them in shape.

While grapefruit plants become more hardy as they mature, a young plant mustn’t be exposed to temperatures below 10°C (50°F). Trees can attain a height of 5m (16ft).
‘Star Ruby’

A good choice because it is less vigorous than other grapefruit cultivars. Its large fruits have deep red, extremely juicy flesh, thin skin, and a very sweet flavour.
Lemon and lime

Of the two lemon species, C. limon is much more cold sensitive than C. x meyeri, which survives down to 5°C (41°F). Limes and C. limon will only tolerate temperatures down to 10°C (50°F).
‘Garey’s Eureka’ (lemon)

A popular cultivar with commercial growers, this lemon produces extremely good and plentiful juice in fruits with few seeds. The very productive tree can be in flower and fruit for most of the year.
‘Tahiti’ (lime)

The small fruits of this lime have an excellent flavour and no seeds. The plants are fairly vigorous, growing to 1.8m (6ft) tall, and extremely productive. The fruits ripen to a pale green.

This is an unusual citrus in that the fruits are eaten whole – skins and all. The plants are naturally very bushy and can be highly productive. They can tolerate winter temperatures down to 7°C (45°F).

This is extremely productive, bearing dozens of small, oval fruits on compact plants. The balance of flavours between the sour flesh and sweet rind makes this kumquat tasty whether cooked or fresh.

Once fully grown the fruit develops a rich skin colour, signifying they’re ready to pick.

They can then be eaten fresh, made into preserves, dried, candied, or preserved in alcohol.
Pests and diseases

Best of luck!

19 Nov, 2009


I have planted some lemon seeds in a pot on the kitchen ledge and they have just started to sprout, I do hope they get like your ones :o))))

19 Nov, 2009


Fantastic, plain and simple, hope they work. I will keep you updated as they grow on... Thanks once again Arlene... very helpful.

23 Nov, 2009


Pleased to have helped!~ I have a small plant which is supposed to be a cross between a lemon and grapefuit ~I think!I have brought it out of the weather into the kitchen and there are a couple of quite large flower buds~ will take a pic when open~ the flowers smell lovely don't they!

23 Nov, 2009

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