Are Wasps a pest or garden natural pest control

August 28, 2008

Wasps are fascinating eusocial insects with a queen and many infertile female workers. I think they are the tigers of the air. Some people consider wasps a pest because they eat the fruit and drink their beer whereas others consider them a welcome garden natural pest control.

As the season comes to an end, they prepare by producing Virgin Queens to carry the genes in to the next generation.

Queen wasp building a nest

Instead of only producing workers to tend the nest, the workers of colony decide to feed some the larva with protein to produce Queens. They want meat. Prey can be caterpillars, or insects, some they rade from spiders webs. They chop the caterpillars into manageable pieces and fly back to the nest where they are chewed up and fed to the larger queen larva. It’s only the larvae that can eat meat, Wasps can’t. The larvae regurgitate a sugary meal in return for being fed by the adult wasps.

Wasps are very useful as natural garden pest control because they eat a large number of garden pests such as caterpillars, aphids, queen ants.

Wasp nest in lawn can be dangerous to humans and pets

Wasp nest in lawn can be dangerous to humans and pets Wasps excavating a mouse hole in lawn

Wasps excavating a mouse hole in a lawn

Wasps excavating a mouse hole in a lawn

Wasps will often make their nests in our loft space, where it is dry and out of the way of danger or under tree roots and sometimes they will excave underground mouse holes. These can be more of a problem because if they are disturbed by people walking on the lawn near the nest or disturbed by the vibrations from a lawn mower, they are more likely to go and defend their nest and sting whatever they consider a danger.

A powder can be sprayed in to the nest – best to do this at night when it’s dark and all the wasps are inside the nest and less able to come out in defence of the nest.  If the colony is causing no danger to humans or pets then best to leave them alone.

In the northern hemisphere only the Queens survive the winter by hibernating and emerge the following spring to start a new colony. All the workers and drones will die.

In New Zealand however, the weather allows the wasp colony to survive all year round and our European or German wasps are causing havoc to their native wildlife.

Photography Neil Bromhall.

The reason for pruning. How to prune and what’s the point of deadheading

August 25, 2008

To grow attractive looking perennial plants most need to be pruned otherwise they become too big, untidy and produce unimpressive flowers.

Many people new to gardening are nervous when it comes to pruning.
This is because there’s a baffling amount of information on pruning and to make things worse some of the information seems to contradict the other.

If you think of it, herbivores have been nibbling at plants for millions of years, so plants are quite used to being nibbled and cut. It’s been suggested that the saliva actually stimulates growth.

Pruning encourages new productive growth

Pruning encourages new productive growth

The reasons for pruning.
Pruning encourages new healthy growth.
If you cut out dying and diseases wood, the plant can instead of fighting disease will put its energy in to new productive growth.
Pruning will keep the plant shape and size in check.
Pruning will keep unwanted seed dispersal under control.

Deadheading encourages a second flush of flowers

Deadheading encourages a second flush of flowers

Pruning / deadheading will encourage a second flush of flowers. The reason being, when you deadhead a flower, the plant can no longer put its energy into seed production. Reproduction is the second imperative so if the plant can’t make seeds because you’ve cut the fertilised flower off, the plant will put it’s energy into producing new flowers in which to do so.
Although flowers are attractive to our eyes, the real function of a flower is to attract insects to transfer pollen from one flower to another, resulting pollination and seed production.
Deadheading basically removes the ability of the plant to produce seeds and so it produces another flush of flowers in order to do so.
Deadheading will produce new flowers in the growing season. Deadheading very late in the season won’t produce further flowers as the plant reacts to the falling light levels and temperature changes and so it’s programmed to shut down ready for dormancy over the winter period.

Some plants won’t produce new growth if you cut in to old wood.
Cut at an angle just above an outward facing bud.
Use sharp secateurs to make a clean cut.  A clean cut will quickly heal quickly whereas a blunt blade will bruise the stem where die-back or disease can set in.

Pruning vines. Some plants like vines will weep sap profusely if you cut in the growing season, so it’s best to cut when the vine is dormant i.e when the sap not rising.
Clematis pruning. There are basically four pruning techniques for pruning clematis.
Rose pruning. There are 4-5 different rose types all needing different pruning

Pruning wisteria. The Wisteria like many vines only produces flowers on the branches that are in direct sunlight. The flowering buds are stimulated to form by the sunlight. Wisteria are therefore pruned twice a year.

To have the answers you want within seconds and to save time searching through books and the internet, illustrated pruning advice accompanies each plant of the 3,500 UK

garden plants on the interactive The Calendar reminds you which plants you have and when and how to prune

them. All the information on the website can be printed with images, plus you can add your own printable notes accompanying each plant.

Used by garden novice to Garden Designer.

Growing Sweet Corn and how you know when to harvest.

August 24, 2008
Sweet corn 'Butterscotch' best eaten just after it's picked
Sweet corn ‘Butterscotch F1’

Plant your sweet corn 2cm deep, in a frost-fee, well drained, fertile soil and sunny position in your allotment or garden. Ideally the pH should be around 6.0 – 6.5

I first soaked the dried corn seeds over night to allow them to absorb water. Then kept the corn in damp kitchen paper for a few days to see which were viable then selected the ones that had started to germinate.

Ideally your plants needs at least eight hours of sunlight a day.
To germinate the soil temperature should be about 60 degrees. You can start planting in pots in the greenhouse then transplanting the seedlings when the soil is warm enough.

Don’t mix up different varieties together as you’ll get cross pollination. Plant the same variety of corn in a block 30cm apart and rows about 60cm apart. The plants need to be close enough together to ensure wind pollination and to ensure they fertilise each other to produce corn on the cob.

Water well throughout the growing season and don’t let the sol dry out.
If our British weather ever gets too hot, water more frequently. The sweet corn will not grow well if it becomes to dry for long periods.

Milkly liquid indicates when the sweet corn is ripe

Milky liquid indicates when the sweet corn is ripe

The time to harvest your sweet corn is when the ‘silks’ are brown and dry and you can pierce the kernels with a finger nail. If the liquid is clear it’s not quite ripe. When you get a milky liquid then it’s the time to pick your corn on the cob by twisting the ears of corn which should snap off the main stem.
Sweet corn just picked

Peel the husks off before boiling your corn on the cob.

The best time to harvest your corn is in the cooler hours of the morning.  Store them in cool temperatures, the cooler the better.

You will get the sweetest flavour if you eat your sweet corn on the cob as soon as possible. BBC prestenter Carol Klein suggests even taking a pan of boiling water to the plant and popping the cob in to the boiling water within seconds.
Boil for 6 minutes. Spread butter and a bit of salt to your taste. Delicious

The variety photographed is Butterscotch F1

Sweet corn mouse damage

Sweet corn mouse damage

Pests: Mice will eat your sweet corn as soon as they are ripe.

Photography Neil Bromhall. This blog is an extension to the Complete gardens planting advice CD-ROM

How to improve the chances of selling your house by doing up the garden

August 21, 2008
Add colour and interest to create a good impression

Add colour and interest to create a good impression

First impressions count.

It’s very important that when the viewer looks at your property they get a good impression. You might not want your garden to look like this one but even this style is easy to create if you know  what plants to use.

Tidy up the garden and add some colourful plants.

Finding the right plants that look great at the right time of year when you want to sell your property isn’t difficult.

The interactive Complete garden plant selector and planting guide CD-ROM has 3,500 garden plants for every aspect of a garden, size, soil type and seasonal need.

Finding the right plants is quick and easy. The best plants are displayed within seconds

Finding the right plants is quick and easy. The best plants are displayed within seconds

The plant database is aimed for the UK market yet has been sold to many parts of the world.

The interactive plant database is very easy to use. You simply select any combination of month/season, flower colour and or leaf colour, height, soil type, aspect or name. Click search and the software searches your requirements and displays the best plants to suit your needs within seconds.

A choice of titles costing less than £50.00. With the simple knowledge of the right plants, right time and place, you can easily add value and interest to your property and use the plant selector and pruning guide to add colour, value and enjoyment to your next home.

In-depth plant care advice and pruning guide plus photographs accompany each plant

In-depth plant care advice and pruning guide plus photographs accompany each plant

Each plant is accompanied with plant care and illustrated pruning advice.

In the Calendar, make your own visual plant lists

You’re reminded what plants you have that need pruning and what to do. The result are healthy looking plants

Add your own notes and print with images

Make visual, printable plant lists

Make visual, printable plant lists

 Print out the visual list plants you want and take it with you to the your local Garden Centre.

The Complete Gardes CD-ROM is both PC & MAC compatible. See the demos to get an idea how the interactive plant database works. The demos on our web site runs much slower than the CD-ROM but give an idea how it works and how easy it is to use.

How to hand Pollinate courgette flowers

August 21, 2008
Pollinating courgette flower by hand

Pollinating courgette flower by hand

In wet weather conditions your courgettes might not get fertilised due to the lack of insects to pollinate the flowers.

Courgette blossom end rot with spores

Courgette blossom end rot with spores

If so, your courgette fruits won’t mature or worse develop blossom end rot.

Courgette flower male and female

Courgette flower male and female

It’s possible to hand pollinate the flowers by brushing the pollen from the male courgette flower on to the stigma of the female flower.

Photography Neil Bromhall. Complete garden planting advice database with 3,500 uk garden plants, vegetables and 9,000 photographs.

Small White ‘Pieris rapae’ Butterfly and caterpillar. Vegetable pest identification

August 21, 2008

Small White Pieris rapae are considered a garden pest as they eat cabbage and tomatoes.

Small White butterfly laying egs on a cabbage

Small White butterfly laying eggs on underside of a cabbage leaf

Small White ‘Pieris rapae’ caterpillars young and old

The caterpillars will eat your brassica as well as your tomato plants.

They are very well camourglaged and difficult to see.

They mainly come out under the safely of darkness to feed.

The caterpillars eat the leaves as well as the unripe tomatoes.

Tomatoes eaten by Pieris rapae caterpillars

Tomatoes eaten by caterpillars

Photography Neil Bromhall.

Are you on Acid

August 19, 2008


Acid loving plants could just as easily and probably more accurately be called lime hating plants. It is the presence of lime or calcium in the soil that causes all the problems.

There is quite a range of popular plants that need acidic soil conditions to thrive. These include plants such as Rhododendron, Pieris, Erica, Pernettya, Kalmia  and Pachysandra. They are often termed Ericaceous plants suggesting they all belong to the family Ericaceae (but there are many others).

Compost for lime hating plants is often called Ericaceous compost.

Plants whose natural habitat is alkaline often grow perfectly well in acid conditions but the converse is not often true.

Soil is classified as being alkaline or acidic by its pH value, for example pH 8. (This term comes from the French word ‘puissance’, meaning power or strength and gives us the ‘p’. The H is for hydrogen. And the number refers to the concentration of Hydrogen ions in the soil.) Below pH 7 is considered acidic and above is considered alkaline. Your soil pH can be tested with a kit using solutions mixed in small tubes where it is judged by the colour it turns or, more conveniently, there are inexpensive electronic probes available.

These you simply push into the soil and take a reading.

A much cruder test but ideal for a quick assessment is to see what is growing either in your own or neighbouring gardens. If there are any of the plants mentioned above then the soil is going to be acid.

A word of warning here. Soil conditions can change over a surprisingly short distance so this method is only a guide.

Symptoms of lime intolerance are often called chlorosis.

Plants need to get energy from the sun. To do this they produce a green pigment called Chlorophyll. This is what makes leaves green. To produce this pigment the plant constructs the chlorophyll molecule based on iron before replacing the iron with nitrogen. So iron and nitrogen are important. Undernourished plants often have pale green or yellow leaves because they do not have enough nitrogen. Give them a feed that contains nitrogen and they will soon green up and look healthy once again-easily cured.

However, too much lime in the soil prevents acid loving plants taking up iron. Without iron there is no green chlorophyll production and the plant looks pale, typically showing yellowing between the leaf veins. No matter how much nitrogen you feed to plants under these conditions they will not green up. 

The Cure.

The obvious way to avoid problems of chlorosis is not to grow acid loving plants on alkaline soil. Knowing this, in regions of alkaline soil, many of us choose to grow our Rhodo’s or Pieris in a pot. This is fine as long as you remember to use ericaceous compost and to be aware that if you are continually using hard or limey tap water to irrigate your plants you will gradually build up the levels of calcium in the compost so raising the pH and making life uncomfortable for your plant. It will eventually show signs of chlorosis. Watering with soft or rain water ( I use water from my dehumidifier for my one and only lime hating plant.) prevents this problem.

In the open garden the soil can be acidified by adding sulphur which in combination with water becomes sulphuric acid. Because there is usually such a great reserve of calcium in alkaline soils this is a fairly temporary measure and if you choose this method you will have to repeat the dose  at regular intervals depending on the level of alkalinity.

An alternative is to use chelated iron compounds of which Sequestrene is a well known brand. This provides the iron in a form that can be taken up by the plant. Again this will need to be applied at regular intervals.


Confused by the terminology?  Alkaline, limey, calcium rich and high pH all mean the same thing and that is that you have lime in your soil and you cannot grow rhododendrons.

High pH can have its advantages. If you are a veg grower then a high pH controls the incidence of club root on Brassicas.

If you live in an area with alkaline soil but are desperate to grow acid loving plants then the best long term solution is to create raised beds that can be filled with an acidic peat enriched soil.

Hydrangeas will grow quite happily in alkaline soils but you will not get blue flowers. In limey soils the aluminium that the Hydrangea needs to produce blue flowers is locked up so the flowers turn out pink. Hydrangea colorants contain aluminium that is available to the plant regardless of soil conditions so turning the flowers blue.

Colorants are available from garden centres.

This articles is just one of the articles found on the interactive plant finder, planting advice and pruning guide CD-ROM The CD-ROM contains 3,500 UK garden plants with 9,000 photographs plus illustrated pruning tips