Hooters Hall

Posts Tagged ‘vegetables’

Growing Vegetables

  Our growing vegetables series of articles aims to take you through the process of growing your own vegetables step by step.

There are six articles in all you can either scroll down this page to find them or click on the links below.

  1. Growing vegetables: part 1 where to grow them http://www.hootershall.co.uk/category/articles/growing-vegetables-articles/page/3/
  2. Growing vegetables: part 2 assessing and preparing the site http://www.hootershall.co.uk/2010/07/22/growing-vegetablespart-2-assessing-and-preparing-the-site/
  3. Growing vegetables: part 3 choosing your veg, crop rotation and planting schemes http://www.hootershall.co.uk/2010/07/26/growing-vegetables-part-3-choosing-your-veg-crop-rotation-and-planting-schemes/
  4. Growing vegetables: part 4 germination http://www.hootershall.co.uk/2010/07/31/growing-vegetablespart-4-germination/
  5. Growing vegetables: part 5 feeding http://www.hootershall.co.uk/2010/08/28/growing-vegetables-part-5-feeding/
  6. Growing vegetables: part 6 green manure http://www.hootershall.co.uk/2010/09/05/growing-vegetables-part-6-green-manure/

Pests and diseases part 6

The next weapon in the organic gardener’s chemical free arsenal against pests and diseases is a physical one. Specifically traps and barriers. At a more basic level physical pest control can simply mean removing the pests by hand. In some cases this can be very sucessful but on a large plot or smallholding isn’t really practical. Traps and barriers work in a number of ways; they can prevent pests reaching your crop, draw them to a more tempting location, some eliminate the pest and others are used to give an indication of when other controls e.g. biological controls might be most effective.

Grease bands are essentially a sticky barrier applied to the trunks of fruit trees to trap winter moths and other related species that have wingless females. Grease bands can also deter earwigs, ants and adult vine weevils. Grease bands can be applied to containers as well as trees. It is also possible to smear grease on the stems of some plants e.g. chrysanthemums and dahlias to stop earwigs climbing up into flowers. Pests such as flea beetles can also be made to jump onto a piece of wood or card covered in grease and drawn grease side down along the top of plants. If the plants are agitated by hand or a stick the flea beetles are disturbed and so jump onto the greased card trap.

Sticky traps are also useful in greenhouses. It’s best to use yellow plastic strips covered in a non drying glue. The traps are hung above the plants and will catch any flying insects. Whilst these traps alone may not control an infestation they provide an early warning system, allowing the gardener to implement other measures such as biological controls before the infestation becomes unmanageable.

Grapefruit and beer traps are useful in the never ending battle against slugs and snails. Hollowed out grapefruit halves can be propped up on stones on the ground in flower beds. The slugs and snails are attracted by the smell, crawl in and stay there. In the morning you can simply remove the grapefruit complete with slugs and snails. A jar half full of beer or milk, almost buried in the ground will also attract slugs and snails which fall in and drown. The addition of porridge oats makes it an even more effective bait.

Earwigs can be trapped by using an inverted flower pot filled with dry grass and placed over a cane among susceptible plants. Earwigs feed at night and will crawl into the trap to shelter from the daylight. Once they have crawled in you can remove the pot complete with earwigs.

Damage from wireworms can be limited by fixing a potato on a stick and burying it. Wireworms prefer potato over plant roots so will preferentially inhabit the potato which can be regularly removed and replaced.   

Pheromone traps use synthetic pheromones of a pest species such as the codling moth to attract male moths into a trap where they are caught on sticky paper. The main purpose of such traps is to record the moth’s main flight and egg laying period accurately so that, if necessary, insecticides can be applied at the appropriate time to control the newly hatched larvae. On an isolated apple or plum tree however the pheromone trap may catch sufficient male moths to limit the mating success of females and so limit the number of fertile eggs produced.

Barriers in the garden can come in a variety of sizes. Fruit cages are one of the largest barriers you can use and will protect your soft fruits from a variety of pests including birds.  On a smaller scale cloches can be used to protect individual plants and can be easily made from lemonade bottles cut in half. Horticultural fleece also provide a relatively inexpensive and flexible barrier method of pest protection as well as protecting against frost.

In the greenhouse putting legs of tables or staging in saucers or pots of water will stop insects climbing up the legs of the table or staging and prevent them reaching your plants. 

Brassica collars can be purchased ready made or you can make your own from carpet, underlay or cardboard. The collar is essentially a circular piece of appropriate material with a cut in it so it can be place around the young plant. The collar lies flat on the soil and prevents the female cabbage root fly from laying its eggs in the soil. instead the eggs are laid on the collar where they will dry up before hatching.

Copper tape is also said to make a useful barrier against slugs and snails when wrapped around containers or raised beds. However, this is relatively expensive compared with the cheap and effective beer/ milk trap described above. 

Pests and diseases part 5

When it comes to mobilising the insect world in the battle against pests I like to think of those wild in the garden as my mercenaries, taking part in the battle in exchange for the nectar and pollen I provide, but ready to move on if they find a better prospect. However, biological controls bought specifically for the job are my crack troops, loyal and focused provided there is an appropriate pest population for them to attack.

Biological control is the use of a pests natural enemy to control it. There are no detrimental effects on beneficial insects, other wildlife, plants or humans. Biological control is specific to the pest and once the pest is eradicated the control will die out. If there is a further infestation you will need to add more biological control.

Biological controls are at their best in a controlled environment such as a greenhouse or polytunnel. Indeed some require a minimum temperature to be effective so outside use is not always feasible in the temperate UK climate. Most biological controls start being active at 10 ºC reaching a peak of activity at 16 ºC  if the temperature falls they will become inactive, but become active again as the temperature rises.

There is no point using a biological control unless the pest is present, otherwise it will just die out. It will take a few weeks for your control to establish itself and have a meaningful effect on pest numbers so it’s always better to introduce the control sooner rather than later if you have an infestation.

There are many garden centres  and online stores that sell biological controls including garden organic. Once you get your biological control they should be used straight away. Don’t use a pesticide in conjunction with biological controls as the pesticide will eradicate the biological control as well. If your infestation is at sucha  level that you want to try and reduce numbers with a pesticide before introducing the biological control choose a short acting natural pesticide.

So which biological control does what ? Here’s a list of the most common commercially reared biological controls, the crops to use them with and the pests they attack.

Aphids General use Aphidoletes aphidimyza Midge
  General use Aphidius spp. Wasp
Caterpillars Brassicas Trichogramma brassicae Wasp
  General use Bacillus thuringiensis Bacterium extract
Flea beetle Brassicas Howardula phyllotreta Nematode
Glasshouse white fly Tomato Macrolophus caliginosus Anthocorid bug
Leaf miner Tomato, Cucumber, Flowers Dacnusa sibirica Wasp
Leaf hopper Tomato Anagrus atomus Wasp
Mealy bug General use Cryptolaemus montrouzieri Ladybird
Red spider mite General use Phytoseiulus persimilis Mite
  General use Amblyseius calfornicus Mite
  General use Feltiella acarisuga Midge
  Tomato, Cucumber Therodiplosis persicae Midge
Sciarid fly General use Steinernema feltiae Nematode
  General use Hypoaspis miles Mite
  General use Bacillus thuringiensis strain Bacterial extract
Silver leaf fungus Top fruit Trichoderma viride Fungus
Slugs General use Phasmarhabditis hermaphrodita Nematode
Thrips Cucumber, Sweet peppers Neoseiulus cucumeris Mite
  Cucumber Orius laevigatus Anthocorid bug
Tomato mosaic virus Tomaro Mild strain of virus  
Vine Weevil General use Steinernema capsicarpae Nematode

And here’s a link to the biological controls available at garden organic.