Noah Chase of Deelish Garden Centre looks at growing plants without the use of chemical pesticides, herbicides and inorganic fertilisers that pollute our soil and water
When I first became involved in the garden centre trade I was shocked to realise how many people wanted to fix the problems in their garden by using chemicals that are harmful to the environment, to the creatures we share this beautiful earth with and to ourselves. As I looked into other possibilities, I was delighted to find there is always an alternative to these heavy handed chemical ‘cures’.
A few years ago we took the decision at Deelish Garden Centre to stop stocking synthetic chemical solutions or quick fixes and to offer only natural alternatives. Our customers’ reaction, when we explained what we were doing, was 99 per cent supportive with many people offering their own experiences and solutions to our growing understanding of sustainable/ responsible gardening.
Essentially, sustainable gardening is growing plants without the use of chemical pesticides, herbicides and inorganic fertilisers that pollute our soil and water. It relies on the use of beneficial insects, diversity of plants, and the use of compost to supply the soil with nutrients.
As Gardeners we have a responsibility and an opportunity to create an environment that supports a diverse range of wild life and plants, and in doing so many of these ‘problems’ will naturally ‘magically’ take care of themselves!
Let’s look at a few ‘problem’ areas of gardening that many people think that they need to use chemicals to solve.
What are weeds? A weed is a plant considered undesirable in a particular situation, ‘a plant in the wrong place’.
Probably the best way to control weeds is the age-old classic of hand weeding but on a large area, this can take quite some time and patience!
Weed killers; here at Deelish we don’t use harmful Glyphosate-based weed killers (or those based on other synthetic chemicals). We’ve trialled several strong vinegar mixes with great results; The weeds were affected the fastest and most completely with full strength vinegar and soap. But you should be aware that vinegar lowers the pH of the soil, making it more acidic. Use it on a hot day and look up recipies online.
We also stock Neudorff weed killer, which is biodegradable (meaning it’s capable of being decomposed in the soil by bacteria or other living organisms and thereby avoiding pollution). The active ingredients are pelargonic acid, which occurs naturally in Pelargoniums and maleic hydrazide.
The application of direct heat to the foliage of weeds will cause the plants to immediately wilt, and repeated applications will kill any leaves that may sprout again from the roots. Flame weed killers are good for this but can be costly to use on a large area.
Using boiling water is an effective method for killing weeds in small areas such as sidewalk or driveway cracks, or over a larger area that you’d like to replant after the weeds are gone, as it doesn’t leave any residue or have any harmful long-term effects.
For paths and drives, we’ve found de-icing salt (sold in 25kg sacks) vey effective when spread on a hot day directly on weeds and in situations where you don’t want new plants to germinate. Don’t use salt where you want to grow other plants – but on pathways and driveways it’s great.
Weed and Feed lawn mixtures generally contain harmful herbicides; many of which have already been banned in many countries. Regular mowing will control most annual weeds; however, it’s ultimately not very sustainable, as an hour of mowing emits as many VOCs and NOx – key precursors to smog – as a typical car driven 45 miles. Tougher perennial weeds such as docks and dandelions can be manually removed (Fruithill Farm supplies a fantastic old style dock digger for larger roots) or removed by one of the methods mentioned above.
For the control of moss in lawns, we’ve found that traditional applications of sulphate of iron, the active ingredient of most popular moss killers, does burn the moss but in the long run creates a more acidic ground in which the moss thrives, making the next batch even harder to control! For a lasting effect, first, proper drainage should be addressed, followed by the application of an indirect biodegradable moss control such as Mo Bacter.
Mo Bacter is an organic fertiliser, which releases its nutrients evenly over a twelve week period. It destroys lawn moss, which doesn’t go black but is digested by the bacteria so that there’s no need to scarify. It’s completely organic, harmless to animals and wildlife, and doesn’t damage border plants.
For feeding lawns here in West Cork, a natural fertiliser with trace elements, such as Greenvale, or one with bacteria like Mo Bacter lawn feed will green up any lawn and feed it for up to 100 days (though be warned this will mean more mowing). And finally, an application of lime early in the season will have a great effect on the health of your lawn and make the soil closer to neutral which will stop moss thriving in acidic damp soil.
In all gardens, there are pests feeding on plants;. however, not all pest damage is significant enough to need action. Even the healthiest gardens encounter pests at one time or another, and so we must consider the level of pest activity that we’re willing to tolerate, and discover ways of keeping a natural balance.
Natural pest control is less expensive than buying and applying pesticides, and it’s safer for your garden, your family, the wildlife and the environment.
There is a huge collection of books and websites written on natural pest control – just have a look online and find which works best in your own garden. However, there are a few general points to remember:
Pull out any weak plants. They may already be affected by disease or a pest. If so, they will attract predators. Pull the plant and dispose of it away from the garden area.
• Build healthy, organic soil. Natural composting methods, mulching and top-dressing your soil with compost or natural fertiliser is the best way to develop strong, vigourous plants. Remember the old organic slogan, feed the soil, not the plant.
• Seaweed mulch or spray. Seaweed contains trace elements such as iron, zinc, barium, calcium, sulphur and magnesium, which promote healthy development in plants. Seaweed fertilizer in mulch or spray form will enhance growth and give plants the strength to withstand disease. Seaweed mulch also repels slugs.
• Minimise insect habitat. Clear garden area of debris and weeds, which are breeding places for insects. Use clean mulch.
• Interplant and rotate crops. Insect pests are often plant specific. When plantings are mixed, pests are less likely to spread throughout a crop. Rotating crops each year is a common method to avoid re-infestation of pests which have over-wintered in the bed.
• Keep foliage dry. Water early so foliage will be dry for most of the day. Wet foliage encourages insect and fungal damage to your plants.
• Disinfect. If you’ve been working with infested plants, clean your tools before moving on to other garden areas. This will reduce the speed of invading insects.
Beneficial insects are insects which you can attract to your garden, or buy from catalogues, which prey on harmful insects or their larvae. There are many different species for specific problems.
Look online for home made insect sprays there are hundreds of recopies out there for every type of pest in the garden. We use Neudorff bug and larvae killer which contains natural Pyrethrums, which come from the flower heads of a Chrysanthemum. Remember that it’s always a good idea to reapply it about 10 days later in case of any larvae hatching out, thus breaking the chain of the pest.
Garlic and or chilli sprays can also be effective, as they will mask the smell of some plants that pests are attracted to. But remember that all sprays, which kill harmful insects, will also kill beneficial insects, so use these homemade remedies selectively, only spraying the infected plants.
For slugs and snails there are many natural options available. On a large scale, Nematodes (tiny wormlike organisms) are very effective; however, after they have feasted on their hosts, they die themselves, and can thus can prove to be quite expensive.
Barriers; some people have found slugs and snails will not cross copper, so if you have some lengths of copper piping, create a barrier with these around your vegtables. Other effective barriers are grease or Vaseline bands around the legs of a table or frame and pots. Dry gorse, pine needles, sharp sand or crushed eggshells and hair are all great barriers. Just create a ring of your chosen material around the plants you want to protect.
Beer traps work really well (they seem to love beer)! Or place a used grapefruit or orange half upside down and the next morning, there should be lots moved in! Discard as you wish…
Going outside at night with a torch will show how many of these pests can be found in just a square meter, (this is a great time to collect them), and just how little damage they do as long as there are other things for them to feed on! For this reason leaving a few plants like lettuce that’s gone to seed as sacrifices is a good option as well.
If you do decide to use pellets (as most gardeners do) please use bird and pet-friendly ones. These usually contain iron phosphate, a compound that also occurs in nature. The more common slug pellets use metaldehyde, which is been banned in some countries, as it can do serious damage to wildlife by getting into the food chain through slug pellets (not a good idea if you are growing vegetables to eat or if you care about wildlife).
I hope to look at other areas in the garden in future articles, as there are many more to consider. For now happy gardening and remember; as gardeners, it’s up to us to look after this beautiful planet for future generations to enjoy!
‘In loving memory of Malcolm Rowley, fly high Mal’