Archive | Pests, Problems and Health

Pests, infections, disease, cultivation and growing problems

Biological Pest Control The Pros and Cons

Biological controls work best when it is warm and activity is highest. The more pests the more there is for the control to eat and treat.


Biological controls are pest predators that can be bought mail order. Once introduced to the greenhouse or garden they can naturally take care of the relevant pest, enabling you to garden organically and free of pests. If you are considering using Biological pest control, these are the pros and cons

Advantages of Biological Control

  • They are totally organic and provide a natural solution to your pests.
  • They can be effective for upto two months.
  • Some biological control you don’t have to buy mail order. E.g. planting marigolds may encourage hoverfly and they will eat aphids.
  • Using Biological control means you won’t kill the natural predators like Thrushes for slugs, and ladybirds for aphids.
  • They don’t create an eyesore like slug pellets do.
  • Saves you having to kill pests, if you are squeamish at going round your lettuce leaves cutting slugs in half.
  • Some insects may develop resistance to domestic sprays.

Disadvantages of Biological Control

Continue Reading →


Dealing With Ants

I am not anti ant but aren’t you glad ants are only small or with their organisation and strength they could rule our gardens.


Photo by David Dennis CC

Ant at work. You have to admire the industry and organisation of ants.

Ants will be a common feature of any garden. To some extent, there is not much you can do about ants. In the garden they are a nuisance, but, sometimes it is just easier to live with them. Ants are more of a problem when they come into the house.

In the garden, you will notice ants, when areas of fine soil are created. (This actually makes very good topsoil). They are unlikely to do much lasting damage to your plants.

Generally, in the garden, I prefer to just tolerate ants, it isn’t really necessary to start using chemicals to kill them.

In the house they are more of a nuisance. But, before resorting to chemicals, simply try to block their entrances and keep areas clean of food.

Ants and Aphids


Photo by Martin Labar CC

This image shows ants and aphids working together. Ants are often attracted by aphids for the juice they excrete. In return, ants help protects aphids from predators.

How to Deal With Ants

  • Ants follow trails of food. Make sure you don’t have trails of food to your house
  • Ants do not manage to cross sticky substances. Using a jelly or slippery grease will prevent ants climbing in.
  • Often the easiest and most effective way of preventing ants entering in the house is to locate the hole where they are managing to enter. (Often ants follow a trail and you can see them returning out the same way they came – carrying food with them.)
  • If you find a colony of ants in a plant pot, you could drench the pot with water. (though make sure you don’t drown your plants.
  • Boiling water on an ant hill may also kill many of the ants in their. Though in the garden it might not be worth it.
  • Use Chemical pesticides.

Book Cover
Ant Spray at


Common Garden Pests

Sometimes we don’t see the pest, but we definitely see their work.

What are the most common garden pests we are likely to encounter and how can we deal with them?


Anyone who has sought to admire their garden, will have come across the devastation that slugs can do. From new shoots of delphiniums to prize hostas and lettuce leaves, slugs can leave a trail of devastation before you can say ‘where are those slug pellets…’
Fortunately, slug populations can be controlled through both the popular slug pellet and more environmentally friendly organic methods. See: Tips for dealing with slugs


There’s not too much difference between slugs and snails when it comes to pests in the garden. I remember my grandma going out in the morning with a plastic bag full of salt, she could easily fill a bag with snails almost every week. The methods for dealing with snails are similar to slugs.

Continue Reading →


Cuckoo Spit and The Froghopper

It is nothing to do with birds or frogs but there is a lot of it about this year.
Cockoo Spit froth containing nymph of Froghopper

Cuckoo spit is the white froth found on plants in early summer. It contains and protects the grub or nymph of the Common Froghopper .
They are called Froghoppers because from above they appear frog-like, and they are able to hop significant distances when disturbed.

Problems Caused by Cuckoo Spit

  • Froghoppers are a pest known particularly to fruit-growers. They feed on plant sap which they extract from the leaves and stems of plants.
  • The grubs causes minor damage in itself, but the insects can carry viruses which can cause serious harm to crops.
  • The eggs are laid on a variety of plants including tender young shoots of Willow, Cherry, Canterbury Bells, Primulas and Apple.
  • Tender shoots and leaves can distort.
  • In gardens they are frequently encountered on such plants as chrysanthemum, dahlia, fuchsia, lavender, rosemary and rose.

Grub on leaf

The immature light green grub can be seen in this froth on the back of this leaf which is now distorted and curling round the wound.

Treatments For Cuckoo Spit

  • Hose off the froth with water or soapy water and the grub will desiccate and die before it can lay its own eggs. Continue Reading →

Understand Mildew in Your Garden

Mildew is an airborne fungus that requires wet weather and warmth to come to life. It is most visible during spring and autumn as the winter is too cold and in summer it may be too hot. The wetter spring and autumn is when the white powdery mold-like mildew shows up most.

When mildew is dormant or being blown around your garden as spores it is invisible. When it has infested your plants it often shows up as a white powdery substance which are dead spores. Black mildew is seen on wood an in damp places in the home whilst yellow patches with brown furry blotches underneath affects Rhododendrons. No plants are immune although some suffer a lot worse than others, roses, gooseberries, marrows, apples, sweet peas, clematis etc.


Tips to Control Mildew

  • It seems contrary but keep plants very well watered at the roots but do not splash the leaves.
  • Stress or lack of air circulation causes mildew to grow & thrive.
  • Mix one tablespoon baking soda with one gallon of water and spray all the plants as a contact fungicide
  • A spray made up with 10% milk and 90% water is not EU approved but is said, after trials, to be effective.
  • Look out for mildew resistant varieties.
  • Mulch when the soil contains plenty of moisture.
  • Do not plant too densely as mildew fungus loves stagnant air.
  • For severe infections, on roses for example, prune out infected parts and white patches on stems immediately. Burn or dispose of all infected debris.

Mildew on Phlox

Effects of Mildew

Lest you think mildew is a benign substance you should be aware of some of its effects.
Corn crops can be devastated by mildew and is of major concern to farmers.
Fruit crops can become mis-shapen and unsaleable.
Severe attacks can and will kill your garden plants.


Gall Midge Cures

Sunflower Stem Midge Gall on Giant Sunflower

Gall midges,  Cecidomyiidae or midge gnats often affect Hemerocallis or Day Lilies.
Midges lay their eggs on the buds which then fail to develop.
The problem is caused by the midge larvae which can be 3mm long. They drop onto the soil where they overwinter as pupae and start the problem next year.

Infected buds get bloated and swell but fail to open. Each bud may contain many larvae. Buds of early-flowering varieties of Daylilies are worst affected.

Other Plants Affected by Gall Midges

      Coneflowers and sunflowers.
      Balsam but I am less worried about a cure for this gall

Cures and Treatment for Gall Midge

  • Pick off or pinch off any infected buds and destroy.
  • Spray with Bug Clear or other insecticide. Bugs in the bud are protected by the bud so spray when midges are laying eggs.
  • Consider growing Day Lilies that flower later in the year. Gall midges lay eggs between late May and June
  • For varieties of gall that affect several other plants then the cures include good husbandry supported by chemicals for large infestations.

5e. Wasp gall
Photo credits
Sunflower Stem Midge Gall on Giant Sunflower by milesizz CC BY-NC-ND 2.0
5e. Wasp gall by kqedquest CC BY-NC 2.0 ‘Parasitic wasps and midges use the undersides of leaves on trees in the dune swail to lay their eggs. These egg packages, called galls, are often brightly colored and can take some interesting shapes.’


Red Spider Mite Control and Prevention

There are a lot of things to go wrong with plants in the greenhouse but a red spider mite infestation is one of the most frustrating. This tomato plant in India has had its day.

Basic Information on Red Spider Mite

  • Plants such as tomatoes, cucumbers and strawberries grown indoors in poly-tunnels or greenhouses are the most susceptible . Apple, peach and plum trees can also suffer.
  • Identifying the mites by the naked eye is difficult but the webs between plant stems often show up when watering or by evening torch light.
  • Plant damage is mainly to the leaves with light mottling, loss of colour and curled edges. This is followed by leaf fall and death or the plant.

Red spider mite (Tetranychus urticae)

Organic Control of Red Spider Mite

  • Keep the atmosphere humid by misting, spraying the underside of leaves and damping down the soil to discourage development and destroy breeding sites.
  • Eliminate over wintering sites by clearing out debris and disinfecting plant pots
  • Hot dry conditions attract red spider mites so give your pot plants some fresh air outside.
  • Use a biological control which breeds faster than the red spider mite and eats them and their eggs as its staple diet. Phytoseiulus persimillis will do the job these insects die when all the mites are eaten so you need new stock each year.
  • Spider mite killer and bio-controls available from Amazon and Tozer seeds.

Red Spider Mite - Mitopus morio

This summer has seen a new control of red spider mites. It is called bad weather.
Red spider mite (Tetranychus urticae) by Gnilenkov Aleksey CC BY 2.0
Red Spider Mite – Mitopus morio by omarrun CC BY 2.0


Grow a Low Allergy Garden – Scent and Smell

Hay fever and Asthma attacks can be brought on by Scented Plants as well as pollen or Fungal Spores. Histamin problems can also be exacerbated by scent and smells in the garden.


Tips to cut Spores and Fungus

  • Ferns reproduce by sending out millions of spores from under the leaves. If you suffer then do not grow any ferns.
  • Fungus and mould are common names for a large variety of mycelium like Alternaria that grow on dead and rotting plants. They reproduce by light invisible spores that are distributed in the air usually in late Summer and Autumn.
  • Reduce the concentration of spores by good husbandry, keep rotting plant matter to a minimum, don’t use bark as a mulch, dustbin infected leaves and more drastically remove hedges that collect spores
  • Compost heaps are home to fungus and ideally should be avoided if you are allergic but a closed system rather than an open pile will be better.
  • Spent mushroom compost can be an allergy disaster – don’t use it.
  • Organic compost and mulch may be a problem but coconut shell is probably one of the lower spore hosts. Compost in a closed container.

Scented Plants are generally pollinated by insects feeding on the nectar. This can include wasps and bees so if you are allergic to stings avoid such plants. Some people are sensitive to a range of smells and perfumes or just the scent of one plants such as a lily or honeysuckle and in this case choosing plants for a garden can be an issue.

  • Aromatic leaved plants like many herbs only give off a scent when brushed or crushed so it may be worth growing herbs but take care with Lavender.
  • If you are allergic to Daisies you will also potentially be allergic to Asters, Chrysanthemeum and other members of the same ‘compositae’ family.
  • Don’t sniff individual plants
  • Many double flowered varieties attract pollination by colour and have less scent.
  • Fruit attract wasps so if allergic to stings don’t grow them or have another member of the family grow them well away from windows into the house.
  • Some allergies are related to individual plants like Strawberries and Tomato so watch for individual reactions and root out offenders.
  • Deciduous trees have more pollen than evergreens.

For a short video watch
Read more about pollen in a low allergy garden

Some top tips from the Asthma society of Ireland for creating an allergy friendly garden include;

1. Choose plants that are pollinated by bees, the pollen is heavier and sticky and therefore stays on the bees rather than floating around the garden.
2. Avoid wind pollinated plants which disperse copious amounts of pollen into the air.
3. Avoid plants which are intensely fragrant as they can be a trigger for allergies and asthma.
4. Choose female plants, as they produce no pollen. Sterile male plants are also a good choice.
5. Grass is a major pollen producer so mow your lawn regularly, before it flowers.
6. Wear a mask when mowing lawn or trimming hedge.
7. If possible replace your lawn with gravel
8. Replace organic mulches with inorganic mulches
9. Avoid ornamental grasses in your planting schemes.
10. Remove hedges which harbour dust, pollen grains and mould spores which can trigger asthma and allergy symptoms.


Allergic to Scented Plants?

Allergies can be exacerbated by plants just ask a hayfever sufferer. Pollen and strong scent often combine together and beware of allergic reactions to your garden plants.


Plants to be Wary Of

Asthma sufferers often complain that it is the scented garden plants that bring out the condition.
Generally it is the heavily fragrant flowers but sometimes it is a single species such as Honeysuckle that cause the problem.
Lilies like the Lilium Regale are one of the best scented flowers but one of the worst culprits for allergies.
The Dianthus family of Carnations, Sweet Williams and Pinks with a spicy scent are known to bring on hay fever.
Although generally unscented, many flowers from the Asteraceae or Daisy family seem to be allergenically toxic to many people. If you suffer then it is best to exclude members of this large family including Asters, Chrysanthemums, Marigolds and other similar looking flowers.
Avoid ornamental grasses heavy in pollen.


Top Low Allergy Flowers

  • Aromatic plants which smell due to essential oils are less likely to cause some allergies but if you are very sensitive it is best to avoid Herbs, Lavender and Eucalyptus. Or at least do not inhale bruised leaves.
  • Winter heather Erica Carnea in white and pink can look stunning from Autumn through winter.
  • Geraniums such as the perennial cranesbill, Johnsons Blue is my favourite.
  • Climbing roses can be a problem but Iceberg has a low level of scent and I have seen Handel and Rambling Rector also recommended.
  • Fuchsia magellanica are available in many varieties
  • Hydrangea macrophylla including cultivars  Ayesha, and Madame Emille Mouillere plus Lacecap varieties give you a wide choice of large flowerheads.
  • Orchids as houseplants have cause allergic reaction.

Todmorden 055

Allergic advice from Thompson Morgan
If you have hay fever, asthma or severe allergies, you should avoid eating flowers of the daisy family because they could trigger an allergic reaction. Take care when choosing a location for mushroom growing as some people are allergic to mushrooms or mushroom spores and others may become sensitised by high concentrations of spores.


Leaf Miners Indoor & Outdoor Pests

Leaf miners have been at work here, NC

Leaf miners are the larvae of moths, beetles, maggots, flies or caterpillars that have hatched between the upper and lower epidermis of a leaf. They then burrow there way out eating part of the leaf and leaving a trail.

Common Types from 524 Leaf Miners

  • Chrysanthemum leaf miner ‘Phytomyza chrysanthemi’ also known as the Margurite fly.
  • Privet leaf miner ‘Gracilaria cuculipennella’
  • Palm leaf miner ‘Homaledra sabelella’
  • Other favourite indoor targets include Ficus species and African Violets.
  • A few mining insects use other parts of a plant, such as the surface of a fruit.
  • The horse chestnut leaf miner ‘Cameraria ohridella’

Damage and Control

  • Deterioration of plants leaf by leaf results from the tunneling or mining activity.
  • Some damage is linear some is serpentine.
  • Blotches and circular ruptures may occur where the surface has been eaten away.
  • Sprays are largely ineffective as the insect is protected under the surface of the leaf.
  • Systemic insecticide is the only cure. Insecticides recommended for leaf miner control on farm crops include carbaryl, chlorfenvinphos, diazinon, dimethoate and trichlorphon.
  • Infected leaves should be pruned off and destroyed.
  • Farmers may reduce or prevent problems by planting trap or distraction crops near the plants to be protected


Jatropha leaf miners

Sources Creative Commons
Top; by Martin LaBar, on Flickr’ leaf miners, insects that, generally as larvae, burrow between the upper and lower epidermis of leaves. An interesting ecological niche!’
Lower; leaf miners by tonrulkens, on Flickr

Read British Leaf Miners


Powered by WordPress. Designed by WooThemes