Organic Food Plant Pest and Parasite control

So far I have had problems with a few different pests. Those are both bug or fungal in nature.

This list is not exhaustive, but is what I have dealt with so far.

• Scale - on my rosemary plants I began to notice small brown spots - tortoiseshell style things. I pried at them with a stick, and saw they came off easily. I looked them up on the net - these are scale - they try to camouflage with the plant. Younger ones are orange. They seem to love attaching themselves to the leaves and stems.


• Aphids - little green blighters that really suck the sap from plants - they are much more decidedly damaging than scale, and multiply really quickly. So far I am finding these the hardest to control.


• Red Spider mites - These are getting into the tops of the tomatoes -when in large numbers they leave webs between the leaves and really damage the leaves.


• Fungus Gnats - Sciarid Fly - the gnats themselves just hover and buzz around distractingly, but their larvae gnaw through roots and kill plants.


• Fusarium - this is a fungal infection in Basil that basically means the basil plant needs to be thrown away. Watch out - supermarket basil growing pots tend to carry this - quarantine them on their own windowsill or area away from other herbs for a few weeks to ensure they dont pass it around.


• Powdery Mildew - I think this fungus moved in on one of my Rosemary plants to accompany a scale problem.


• Some horrible, and yet unidentified problem I had with one batch of basil plants - long gone now, but these things, grub like in form, were popping up as cysts on the stem, and could be pulled off - please let me know if you know what they were.

I have been trying many ways to deal with pests. Here is a list of them. I will continue adding detail as I learn more about them.

• Careful watering - overwatering or watering at the wrong time can leave standing water, and be a magnet for fungi and some pests.


• Pulling them off with a scraper or instrument - limited success, takes a lot of work. With fungus gnats, this means digging around the roots of potted plants to get the larvae out - which may damage the roots as much as the larvae would anyway. With Spider Mites, great care must be taken not to damage stems or tear leaves - not a very effective technique. It is good at least to remove the webbing they leave.


• Sundew plants - can catch flying things. Pulling off insects and feeding them to it is not such a good idea, read below for more.


• Venus Flytrap - these are huge fun, and will catch big flies and creatures. They are a bit less useful for smaller things like fungus gnats so while fun, do not really control pests.


• Pitcher Plant- yet to try these, if anything they may be able to accompany the scraping off or shaking off as a receptacle for the pests. There is something that would be satisfying about feeding them to a plant.


• Sticky fly traps - while I try to keep it organic, the kind of traps that come with sticks to hold small sticky squares are pretty handy. They catch fungus gnats. These are kept well away from leaves, soil and plant stems, and mean introducing nothing to the soil.


• Squirty concoctions - I would rather keep plants organic, and if I am to spray them with anything, then it will be something I made myself. Read below for more on this. I think using Chilli powder, salt, pepper, herbs, lemon rind or similar remedies suggested around the internet probably falls into this category.


• Spiders - if I find spiders in the flat that need relocating, they get relocated to my plants. I am not sure if they will eat Aphids, but it is worth a shot.


• Fly swatter - only really good for big flies, although they can be used to blat the occasional fungus gnat. Satisfying but not really of much use.


• Advice found online suggests that if you can, grow some flowering plants around your food and leave the window open in the summer months to encourage both bees and ladybirds. Bees will help pollinate your plants, and ladybirds will eat pests on them. So far I have had few bees or Ladybird in my patch, but then tomatoes are the main flowering plant.

Sundews are carnivorous plants which look great and seem a bit less intimidating than the Venus Flytrap. After buying one, I thought it a good idea to feed it the Aphids that were giving my parsley a hard time.

I manually scraped many off and dutifully fed them to the Sundew.

This is a HUGE mistake - don't do it! Far from being a tasty snack for the Sundew, the Aphids actually have after a week or two taken over, the Sundew is dry and its leaves are blackening. So do not be tempted to put Aphids into a Sundew.

Perhaps I shall try a pitcher plant for this next time.

As you may have read in my other lens Growing Tomatoes(and other stuff) I am currently experiencing an infestation of these little things.

They are small, black, hovery little things. They will land anywhere, and lay eggs in soil. Their larvae tend to eat plant roots, but worse still, the adults may die on soil, and immediately start to sprout white fungal tendrils. I had it full scale - they were slowly gaining in numbers, they were emerging from soil, and little white furry winged carcasses were turning up around the bases of my plants.

Before I saw the white carcasses I knew these were fungus gnats - I have seen them before. Being small, black and hovery, they can be mistaken for fruit fly. However, if you try the Jam Jar honey trap, they will pretty much show a distinct disinterest, unlike the fruit fly.

I have been swatting them, but this only gets rid of one or two, and tends to leave fly guts to be cleaned off hands, windows and walls - not good.

So I bought some of the yellow sticky paper above. Unable to find the small squares of it with special holders, I decided to improvise. I bought the large sheets (all the local DIY store had) and cut it into squares about 3cm in size. I then took some barbecue skewers.

I first tried to make grooves around the barbecue skewers and wedge the sticky paper around this - but that failed to stay put. So my other attempt I then decided to snap the skewers to about 6-7cms in length, and then use some scissors to hack (watch your fingers doing this - I was careful, but this is a bit of an abuse of the tool) a split in one end. I then pulled both sides of the backing off the sticky paper, and wedged it firmly into the split. I then pushed the other end of the skewer into the soil.

As I did this, my efforts disturbed things enough that I was getting immediate results. So I replaced any old fly papers I had, and proceeded to apply this to all the pots around.

One thing worth noting - the large greenhouse sticky paper (or plastic I suppose) has some non sticky sections intended for fastening. For this application, I trimmed that away, thus ensuring that most places the flies would land was a trap.

I have also collected a few toilet rolls, and will be building some traps with this too. Basically - the more square meters of sticky stuff to land on, hopefully the fewer flies will live long enough to breed.

I have been, in the name of hygiene continually removing full paper, and fly carcasses from plants. I do not want my plants to get a fungal infection which may seriously harm them - I have already lost a couple of basil plants to a bacterial leaf infection, and a rosemary to a fungi/scale attack. The other rosemary survived, but I am reluctant to eat the herb until I am sure it is clear of fungal infection.

During a lunch hour trip to a small garden centre in West Kensington, I was chatting with a colleague about the Aphids in my parsley, and now more seriously my Sundew. The Aphids appear to have done a great deal more harm to the sundew than they were doing to the parsley.

As I did so, a kindly old lady who couldn't help but hear, advised me that Chives are a good repellent for Aphids. Apparently - they cannot stand the smell of them, so having clumps of chives in pots among the other plants will get rid of them.

Having a few clumps of chives, which I had even pictured in background behind my Sundew, I was able to quickly rectify this and place the Sundew and parsley very close to the chives (which need a trim now anyway). I am yet to see if this will help.

Well the good news is that my tomato plants are still making edible fruit and flowering well into December - in England. However, they are indoor plants so they are protected from the frost, but they cannot be getting that much sunlight. They are in a north facing window.

Since my last update I had an attack of Red Spider Mites. I noticed my plants were under attack - and the smaller seedlings were in real trouble. I looked and could see little webs around them. My initial thought was some kind of fungal or bacterial infection, as I had feared in October. But trawling the web and looking closer, I could see the little blighters. What they do is feed on the plants, damaging the cells as they do - first there will be spots, then colourless patches, then leaves will die. It was a major infection.

Reading about them, I found they like dry conditions, which was a problem because fungus gnats like moist conditions. How would I deal with them? My initial instinct was to separate the plants more, but once I found out about them, it was better to let the plants remain closer- so the heat and humidity between them would increase. I was brushing away the webs, and the undersides of leaves regularly. I also found a ladybird in the house and introduced it to my window area. The spider mites have since began to decline, or be manageable - so this is less of a problem.

The fungus gnats however are still there. My idea of covering pots with sticky stuff worked a little, but was not great. It caused problems, obvious ones, with watering and feeding plants.

I tried turning each pot into a trap - wrapping the tape (which was not particularly sticky) around the outside of pots. The flies were simply not sticking to that - it had no effect.

My next idea was to try newspaper - I reasoned that since gnats lay eggs in soil, covering the soil would prevent them laying and emerging. How wrong I was! The plants which were covered ended up somehow with much larger populations of gnat larvae, which simply eat through the paper. The paper itself began to show mould/fungi - so it had to go. So much for that idea.

I had at this point left the sticky traps around the drip trays of the pots, and noticed that some of those were absolutely black with dead flies. So my next trick now, having removed the newspaper, was to try sticky trap strips around the plant pots - which seems to be doing OK. I will have to see what I can do next - but these gnats are just not going away.

Sadly - my sundew succumbed completely to the aphids, as did the parsley - both of which I ditched, but kept the pots. The Venus Flytrap is on its last legs - it does not like the cold weather, or it does not like how dry it can become when the heating is on.

The rubber plant lost most of its foliage due to the spider mites - and I lost whole trusses of flowers as well as leaves to it on the tomato plants - so while the problem was short lived, they really did cause havoc.

The scale in the rosemary seems to have died - although the rosemary will need some care to recover. It seems that it may have a fungal problem - powdery mildew - so it is not edible, and may have to be ditched too.

I will have to continue to learn more about these pests and their prevention - using means that are organic. I will share my findings here.

So despite my best efforts, both the fungus gnats and the red spider mites are still about. The populations of both are lower due to slightly cooler weather. However, both are on the move and gaining in numbers again.

The rubber plant is recovering at least.

The Venus Fly Trap died - due to not having enough light, and possibly not being wet enough. A garden centre advised that they rarely survive a British winter, but it was indoors. I will get another one next year - I love those plants.

The aphids are gone, only because all the food they like has also gone. They do not like chives, which are near the tomatoes, and are not keen on tomatoes, rubber plants or cacti it seems. So there is some good news.

The sticky traps had caught many flies, but they were not really dying off. I was also able to brush off spider mites with my fingers fairly often, and still even finding webs in the plants. Time for a bigger solution.

I went to the defenders site - who specialise in biological pest control. I purchased two strains of mites - Phytoseiulus which feed on all stages of the Red Spider Mite and Hypoaspis which are predators of Fungus gnat larvae.

Today - 6th January, I have deployed the Hypoaspis in the soil, and the Phytoseiulus in the leaves. I asked the defenders to ensure that the two species can coexist, which they can. I think that the dose of Phytoseiulus was a little low, but I will wait a few weeks and see if their population grows enough to seriously reap the Spider Mites.

Deploying them - the Hypoaspis (anti fungus gnats) was relatively easy, slowly rotate the container at a 60 degree angle, then open the stopper. The stopper was however a bit hard to open. Then they could simply be shaken onto the soil with the perlite they came in.

The Phtoseiulus (anti red spider mite) were harder. Setup was to leave the tube horizontal for a few minutes, then slowly rotate at 60 degrees again. Then it was a case of opening the stopper (this was a smaller tube so it was easy). Immediately I could see these little blighters moseying on out. The instruction said to let the hole touch leaves for a few seconds so they can get a good grip and find their pray. It said to allow around 5 go on each leaf - this is tiring work, holding a tube at a leaf for a few seconds then moving to another. Sounds easy? Try holding your hand in one place for 5 seconds, now try it 20 times. However, the tube is mostly deployed. To ensure that any still in the tube find somewhere to go, I tied the tube horizontally on a bamboo pole that goes across a few tomato plants, so any stragglers can carry one out and populate those plants.

This I hope should make a real difference, and still without using any pesticides.

Now is a state of flux. I am in the process of embarking on a new gardening experiment, which I am yet to write up. However the results are in on my attempts to use biological pest controls.

Overall - it was a mistake to attempt this over the winter period, when it is harder for the control mites to reproduce and grow in numbers. They are very sensitive to temperature, humidity and conditions, which on the set of plants I treated, on a living room windowsill, are fairly head to control with any certainty. As anyone in London may tell you, the last month or so has had very surprising and changeable weather conditions.

The Fungus Gnat control, Hypoaspis has worked a treat. I see the occasional gnat, but not enough to be at all concerned about. I am observing the control mites on the plants, and can see there is a relatively healthy population of them. If the gnats dies off completely, there is a danger that the mites will also do so, and then the gnats will return. Hopefully, there will be a small population of gnats, feeding a similar population of mites, and a balance will prevail that prevents any gnat population explosions again. This was a really good investment, and I highly recommend other gardeners try this.

The Red Spider Mite Control, Phtoseiulus has not done so well. They depopulated one or two plants, but did not really reproduce themselves - the population of control mites does not appear to have grown. I am still finding plenty of red spider mites and their damage. I realise that I could have dosed better, and that a larger starter population may have been necessary. These were also the more sensitive to conditions, so may have been less effective.

My new planting system that I am experimenting will bring all the plants in closer proximity with a shared soil area. This may mean that parasites are more shared, but then so will the controls. Also the new system will mean that many different species and types of veg will be grown together, so it will be less sensitive to the damage by one parasite and may even repel them. Chives will be part of the plot.

The fungus gnats are gone, beyond the odd straggler, however, my new planting experiment means that there is new soil, so I may need to re-establish a population of predators for them. There number may be on the rise again if I don't.

I am still seeing some numbers of Red spider mites, although they seem to be declining. I am still interested in buying some more spider mite predators when they are available.

Since I am growing everything from seed, and not using growing pots from supermarkets (since last year), I have seen far fewer pests. When I used the new compost there was an initial number of fungi which I was quickly able to remove - they were small grey/white toadstools.

Also now it is in the spring months and soon to be summer, I will be opening the window, and I am considering a bug house to encourage beneficial insects like bees, ladybirds and lacewings.

For sweeter toothed insects, like fruit flies, a honey trap is an old method of catching them.

Many flying insects are attracted to sweet or strong smells as they are constantly foraging. They also not really very bright. This trap uses an interesting smelling substance as a lure to get flies into a jar. It then uses a simple deception to make it hard to get out again.

A cone, with a hole at the bottom, ie a funnel allows them to get into the jar pretty easily. Once in, they will find it hard to find the opening again.

The simplest lure can be a little honey mixed with a little vinegar which will be pretty pungent, but only when close.

Items Required:

• A Jam, Honey or Pickle Jar - It does not need to be cleaned - as the dregs of the original contents can form the lure.
  
  You do not need the jars lid, so you can discard the top or put it aside for other frugal uses (a drip tray for smaller plants maybe).


• A sheet of paper- any non absorbent paper - magazine, yellow pages, scrap, newspaper will do. You want about an A4 sheets worth.


• Sticky Tape


• Vinegar

Step One
Now take the paper, and roll a wide cone, with an opening in the bottom. It should be wide enough that it can sit in the jar, with the hole in the jar, and the hole well above the bait.
Tape up the join in the cone thoroughly.

Step Two
Now put the vinegar in the jar, mixing it a little with the dregs of what was inside. If the jar was already clean, add a little jam or honey.

This mix will be a bit whiffy - you have been warned.

Step Three
Now pop the cone onto the jar. As mentioned in step one, it should be wide enough that it sits here without the end of the cone actually coming into contact with the bait.

Step Four

Tape the paper cone firmly into the jar - it is important that you do not leave any gaps around the sides here, otherwise flies can escape and the trap will fail.

The only way in or out of the jar should now be the opening at the bottom of the funnel, and when near the jar you should be able to smell the lure clearly.

Setting up

Place the jar (or jars if you make more than one) at the site where there are the most critters. If you leave it overnight, in the morning you will have trapped many.

You probably want to clean and remake the jar every few days - first to stop it becoming rotten and too pungent, and second so you do not leave mouldering dead flies around.

It is worth noting that not all flies, or types of flies will be attracted to the sell. My experience has shown that fruit flies and house flies go for this, but not fungus gnats. I am considering a layer of damp, rich soil instead of honey may attract the gnats.

The lens How to Reuse-Toilet-Paper Rolls has plenty of great tips, among them, using a toilet roll tube to make a pest trap. Basically, you take the tube, and cover it with tape sticky side out.

I suspect you could even go a bit further, and make loops of tape facing inward. This would mean flies could get inside, and probably end up trapped before they could get out.

I found it effective to invert tape this way around plant pots. However, the stickiness of the tape used makes a huge difference. Normal parcel tape seems to barely present enough of a problem to Sciarid Fly (Fungus Gnats) to make a difference. Gaffa Tape or duct tape however did a better job.