The changing environmental conditions lately have provided ideal conditions for a few of our garden enemies – powdery mildew and aphids.

In most cases of infestation, its just bad luck pure and simple but prevention is better than cure and understanding their biology and knowing how to care for plants to ensure strong, healthy growth that is more resistant to attack can be a plant life saver.

However, don’t worry if you turned your back for a few days and returned to find pest and/or disease have taken hold – they are most often easily treated with chemical (and non-chemical) controls.

Amongst all this rain, the spell of hot, dry May weather seems like a distant memory.

You wouldn't expect a fungal disease with ‘mildew’ in its name to be associated with dry weather but powdery mildew often appears when plants are under drought stress.

The fungal spores of powdery mildew have an unusually high water content which enables them to infect plants under very dry conditions.

This fungus presents itself as a white bloom covering leaves, flowers and fruit.

On some species, such as roses, the growth of affected tissues can become distorted or stunted.

Mulching and watering can reduce drought stress and make plants less prone to infection.

When watering, its important to water at the base of the plant – avoid overhead watering as this can splash up fungal spores spreading the infection further.

Remove and destroy infected leaves promptly (bin them, don't compost them) and prune out any badly affected shoots.

If you’re happy to go the chemical route (on ornamentals maybe but I’d stay away from chemicals on edibles) there are lots of fungicides on the market that are approved for the control of powdery mildew and some can even be used early as a preventive measure.

Think of it like a plants equivalent to the winter flu jab.

Then the hot, dry weather passed and the rain returned and we breathed a small sigh of relief because it saved us hours of watering.

Unfortunately, the cool temperatures and extra moisture encourages lush, green growth – an aphids favourite meal.

These common sap sucking beasties are known by a couple of different names: blackfly, greenfly and aphid.

But all translate to mean one thing – bad news for plants. You normally find them colonising shoot tips, buds and the underside of leaves.

Infestations cause distortion of plant tissues and stunted growth that can weaken plants if left unchecked. And severe aphid infestations tend to go hand in hand with black sooty moulds which grow on leaf surfaces coated in sticky honeydew, excreted from the aphids bodies.

Under glass, introducing bio controls (natural predators of aphids) can work well but you’ve little hope of success with this method outside.

There is one other well known (disgusting) non chemical control such as squashing the little blighters between your thumb and forefinger but often when it comes to aphids in the garden, chemical treatments are most successful.

These can be broadly split into two groups – contact and systemic.

The former kills aphids on contact and so you’ll need to spray them all to get rid of the problem.

The latter is absorbed by plant tissues first and then by aphids feeding on plant tissues.

Both are effective but there is something extremely satisfying about the irony of killing off the little demons by poisoning them via their food source without actually harming the plant.