Affiliation between RHS and Gardeners Association

The Royal Horticultural Society, to which the NLWGA is affiliated, is seeking closer links with associations like ours, were they are able to provide solutions to gardening problems that many of us amateur gardeners cannot. Furthermore, the RHS will advise on new problems facing gardeners (such as the spread of the New Zealand flatworm that devastates earthworm populations) and possible solutions. They are also seeking our help in gathering country-wide information.

Our committee member Malcolm Greenhalgh has recently taken on the role of linking between us and the RHS and below are some of the recent problems they have advised about. We will try and update the site regularly with further details. If you have comments or experience with any of these please feel free to add your comments by using the comment links. Hopefully we can all benefit from our affiliation with the RHS by learning that little bit more about the plants that we grow. We will collate and feed back to the RHS.

If you have experienced other gardening issues you would like Malcolm to take up with the RHS please email details of these to us using the email links below, and we will endeavor to seek their advice and post  response for all to read and learn from

RHS Membership can be yours at a discount price, and our Association will make a fiver if you do! Advantages: 12 issues of The Garden every year (the best gardening magazine); free entry into RHS gardens (as at Harlow Carr and Wisley); members’ day at RHS shows (e.g. Tatton); a free advice service. If you are interested, please contact Malcolm Greenhalgh.

Codlin Moth on Apples and Pears

by Malcolm Greenhalgh on 05/18/12

Members have asked the best way to avoid the catapillars form these moth burrowing into apples and pears and spoiling them. Note these are different from the winter moths. They feed on very small apples and shoot tips. We stop them by preventing the females ,which are flightless, from laying eggs by having a grease band around the trunk during the winter months. In Codlin moths both the male and female can fly.

The RHS recommends the codli (or codling) moth pheromone trps to work out when these moths are on the wing (usually June). the traps contain a samole of female codlin moth pheromone (sex homone) that attracts the sex mad males. and they stick to the trap. Note that no other moths are attracted. So put out your traps in the second half of May and check it every morning, especially as May turns to June. You can buy these trtaps at our sales hut.

Then when you see trapped males, spray the apple or pear  tree with a systemic incecticide that is concocted to kill catapillars. Three weeks latter give another spray to your trees.

 These trapsd will of course reduce the number of males avaiable for fertilizing the female eggs, but sufficient males usually escape being trapped for damage still to occur.so you need to spray alas for sucess.



Should we Water our Beetroot with Salt Water?

by Malcolm Greenhalgh on 03/06/12

Despite the fact that Bob Flowerdew has recommended that we do this in a magazine article, the RHS recommend that we dont. Sodium Chloride can damage the soil for other crops and the RHS says that the variety of beetroot and age at which it is harvested are far more important to the taste.

Leek moth has arrived and is spreading

by Malcolm Greenhalgh on 01/23/12

Leek moth has arrived and is spreading. Holes appear in the leaves of leeks (it also affects onions) and then the tiny catapillars burrow down into the leek or onion base causing it to rot. There is no good chemical cure, but the adult moth cannot get through the finest insect netting (available for the Sales hut) to lay its eggs. Please let us know if you leeks/onions become affected as the RHS are collecting date on its spread.

In March 2012 the RHS reports that this awful pest has reached Derbyshire, and perhaps further north, so that we can expect it here within the next season or two. The adult moth is tiny and lays eggs on the leaves of leeks, garlic, shallots and onions. The lavae burrow inside the stem/bulb and secondary infection by fungi results in rotting and the loss of the crop. There are two generations of moth per annum, one that seems not too bad in May-June and the other, far worse, in August. Of course our onions, garlic and shallots are drying out and safe in August: hence its far greater impact on leeks. There is no chemical means of killing moth or lavae availablel to gardeners. Instead the RHS recommend that we completely enclose our crops in the fine ecomesh (available at the sales hut).


Minute species of mite kills Fuschia plants

by Malcolm Greenhalgh on 01/23/12

A minute species of mite (part of the spider group) that kills Fuschia plants, arrived on our shores a few month ago is slowly spreading north. This causes great malformation of the growing tip and then death of the plant. If any of your Fushias die  please let us know as the RHS is gathering information about this dreadful newcomer.


Impatiens Downy Mildew

by Malcolm Greenhalgh on 11/25/11

The RHS is warning gardeners not to plant Impatiens commonly known as "Busy Lizzies" in 2012  (or 2013) because of a devastating fungal desease "Downy Mildew" that kills this species is out of control in the UK and resistant to all fungasides. So don't waist either time or money as there are lots of alternatives including a wide range of begonias. The idea is that if we dont grow the host plant (Busy Lizzy) then the disease will die out. Note some seed and plant catalogues have advertised busy lizzies and they have been given some stick by the gardening press.

Affected leaves turn yellow and are rapidly shed from the plant. A fine fungus growth may be visible on the lower leaf surface, but affected leaves decay rapidly. Commonly reducing plants to bare branches and eventual death.

It is most likely to have arrived in the UK on imported commercially propogated material and rapidly become resistance to the commercial fungicides with infected plants then sold widely. As spores can survive for at least a year is is recommend that impatents are not grown at least in 2012.

Yellow spots on young Parsnip Leaves

by Malcolm Greenhalgh on 06/06/11

This year is the first time in almost fifty years of growing them the first two or three true leaves on my parsnips had tiny yellow speckles in the usual green.I checked a few references, and found that the only similar condition occurrs in carrots, and that when it occurs the plants fail to produce carrots. So I called the RHS helpline and was asked to send a leaf sample to the Plant Pathology Dept at Wisley. They emailed back with 24 hrs of receiving the sample to confirm that the speckling was caused by a virus, passed on by aphids, and that my crop should be fine but that I ought keep a careful watch. Since then the parsnips plants have produced good leaves and seem healthy enough. My carrots are unaffected ( I keep them under fleece anyway to avoid the dreaded carrot root fly, so the aphids cannot reach them.)

Recent problems and advice