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Q. I have trees that did not come into leaf in recent years and i think they died during the winter... More »Ans. Trees that stand in water for periods of as little as a week or two can suffer damage to the roots by deprivation of oxygen. The roots can die and the tree can die and not come into leaf. Even if it does come into leaf in spring, it can die soon after. Partly damaged trees can struggle, and carry small leaves, and may survive. Make sure that trees do not stand in waterlogged or flooded soil. Improve drainage if necessary, or unblock existing drains. ...More »
Q. Something is eating all my snowdrop flowers? Any idea what it could be? ... More »Ans. Snowdrop flowers, like daffodil flowers, are often attacked during mild spells by snails. They feed at night and hide by day, although sometimes a small snail can be found tucked into a daffodil flower. Usually there is good cover nearby the damaged clump to allow the snails to hide, while clumps in the open may be unharmed. ...More »
Q. My lemon tree which has given lemons in the past is now looking very sad with sticky glue on the leaves and black dust sticking to it... More »Ans.
The problem you describe is very common with lemon trees in a porch or greenhouse. Almost invariably they suffer from attacks by scale insects which release the sticky glue. Soon after, fungi called ‘sooty moulds’ begin to grow on the sugary glue. The best way to control the problem is to watch for scale insects, or greenflies which also cause the problem, and treat them with Derris or Malathion. The glue and black mould is difficult to remove but sponging with lukewarm water helps … if you have the patience!...More »
Q. In recent years, I have noticed that moss is a much bigger problem... More »Ans.
Moss thrives in moist conditions and usually it peaks in autumn and spring, but with mild winters it has been active for most of the winter months too. Also as a garden ages, more shade is cast by growing trees. Another factor is the soil under lawns becomes acidic and low in nutrients, both of which favour moss growth.
To reduce moss, reduce the amount of shade falling on the lawn area, feed the grass with lawn fertilizer in March and at least one or twice more at two month intervals. Moss can be controlled by applying sulphate of iron at 5 to 10 grams per square metre, either by itself (which is tricky to do), or diluted with water, or mixed with sand. Ready-mixed lawn sand can also be used. But sulphate of iron will not control moss unless the grass is given adequate feeding, and better light.
Q. I have space in my garden for an apple tree but I am told that one is no good as it will need a pollinator beside it... More »Ans. If you live in an urban area, there will be plenty of apple trees, fruiting kind or flowering kind, that will be available to pollinate your tree. It is perfectly possible to plant just one tree in these circumstances and a good variety to use would be 'Discovery', a lovely red apple that ripens in late August. ...More »
Q. For a number of years, I have had a lot of trouble with blackspot on roses... More »Ans.
Blackspot is a real problem and even worse nowadays as air pollution is reduced … the sulphur in oil helped to reduce the problem. Most varieties of bedding roses are affected so it is a choice of either stop growing roses or spraying them with fungicide to achieve control of the disease. There are some varieties that are resistantbut if yours are already affected , those are not among the resistant kinds...More »
Q. I believe there are blight-resistant potatoes now that you do not have to spray for blight... More »Ans.
Yes, there are some exciting varieties that have arrived on the market in recent years. A good early variety, bred in Ireland, with good resistance is ‘Orla’. ‘Cara’ has some resistance too, and the Sarpo varieties, ‘Mira’ and ‘Axona’ are exceptionally good. Mr Middleton in Dublin stocks these....More »
Q. Is it possible to cut down a rubber plant that has grown too tall or would it look bad? ... More »Ans.
Rubber plant is capable of growing to well over 15 metres in the wild, and in a house it can easily reach the ceiling when grown in a pot. It is possible to cut it right back and it will re-sprout and make new branches and a nice bushy shape.
This can be done in March or April, just as the growing season gets going. It is almost always a good plan to re-pot into a larger pot, using half garden soil and half compost.
Keep the plant, after pruning, in a bright sunny place, even if it has no leaves left, and keep it just nicely moist and feed it when the first new shoots appear. It takes a full growing season to make some new growth and will look great after a second summer....More »
Q. I am thinking of making a small rockery near the front of the house... More »Ans.
First of all, a small rockery does not take a great deal of maintenance, such as weeding, and it can be a very pretty decorative feature in the right place, and that is the key to making a decision about a small rock garden. Because the plants are small, they cannot be seen from much distance. So it is always best to place a rock garden in a place where it can be seen and value got from it.
Usually a good place is close to a paved area, which itself is usually close to the house, where it can be seen. Whether the front of the house is a good place needs to be considered. It can be fine because the area can be seen on passing into and out of the house....More »
Q. Hi Gerry... More »Ans.
Wisteria is a fast grower when it is happy in the conditions in which it is grown. If it is not growing well, it might be in need of some feeding, which can be any sort of plant food that you have available, as per instructions.
But lack of nutrients is not always the cause of poor growth. If the soil is too heavy or too wet for a wisteria, it will not grow well and may even die as the roots are denied air in wet ground.
Another problem can be planting too deeply ... check the topmost root is not more than two centimetres below the soil surface. If it is too deeply planted, lift the plant in late autumn and re-plant, setting it a little higher.
You can read more information here:...More »
Q. Hi Gerry, my acer (in large pot) seems dead - no growth obvious this season, and water in saucer under pot never seems to dry up even in dry windy weather... More »Ans. Acer can be tricky in a pot, and even in the open ground sometimes. If a plant is struggling with unsuitable conditions, especially overly wet ground, it can suddenly die. This usually occurs because some roots die, due to lack of oxygen in wet soil, and the dead roots are invaded by a root-rotting fungus. Acer can also die because a fungus, usually coral spot fungus, invades the stem at ground level. The third possibility is that, if the plant was too dry during summer, it may not have made enough storage sugars to keep it going for the entire winter and it dies. However, wait and see if there is any new growth, but if the twigs are dry and brittle, it is probably gone. Occasionally, a plant may sprout from lower down and only the top or some branches die. ...More »
Q. I have a small daphne 'rubra' on a sunny patio in a pot... More »Ans.
Daphne is a plant that likes the soil to be well-drained but it also likes to root deeply and does not like like dry soil. It likes the soil to have plenty of humus and be crumbly and open, and cool.Conditions in a pot tend to be dry, low in humus and hot. Plant it out in the open or, if this is not possible, place the pot in a spot where there is some nice cool shade, and don not neglect watering. ...More »
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