Question Plants/herbs for pest management - potatoes

[The Rubber Kitty]

G'day,

I have had some of my potatoes (kipflers) have these yellow insects on them... they don't look like aphids .. .kinda like little yellow trilobites ... They don't appear to be interested in the Radishes in the same bed that I am growing in.

Are there any good companion plants/ herbs/crops that can help with this or a good safe pesticide?

I know that Mark had mentioned some of them on one of his videos. I am hoping to companion plants something preferably.

I have some lavender in some of my beds ... some generic herbs/companion plants also good in general? and what works well with what?

 

[ClissAT]

Hi Kitty, hard to know exactly what your yellow insects might be.
Potatoes can be affected by white flies which congregate under leaves but every so often when disturbed will all take to the air.
If the leaves are beginning to turn yellow, best to just remove them all along with the critters into a plastic bag then into the bin.
Leave the potatoes to continue to mature for a few weeks in the ground or growing medium. Some might send up new shoots but as long as they are well covered by soil, they are ok to eat.
If they are still young, I would firstly remove half the leaves down to ground level the way I described above.
Then make a 5% soapy solution to spray under the remaining leaves. You may have to spray that a few times to be properly effective.
It will just block the breathing mechanisms of the insects.

Soap solution:- 1tbsp liquid dish or hand soap to 20tbsp warm water in a bottle, that's a 5% solution. Agitaye gently so as to not make a foam. You can multiply those figures to make a larger volume. 10ml soap to 200 ml water. It that strength burns the leaves, half the soap amount. Use low phosphate soap. The label will say low or no phos or make liquid soap by grating sunlight soap into hot water and leaving to soften then stir gently with a fork 1:20 soap to water ratio. Then make your 5% solution from that.

Spray the underside of leaves and stems where insects congregate. The easiest way to get the underside of leaves is to run your arm over the branches or leaves to gently press them down exposing their undersides.


As far as suitable herbs are concerned, it is far better to have mature herbs already growing when you put in your veg. Mature herbs have a full potential of combatants available to protect the young vegie plants. Planting young herbs won't help the existing mature vegie plants which already have put out a registration to alert the critters.

 

[Patty]

I agree with ClissAT, I have also used the soap solution and it works quite well. Not just once, mind you. This was something I had to do weekly for about 6 weeks. Sometimes I sprayed again after a long rain. It helps a lot.

 

[The Rubber Kitty]

Thanks
@ClissAT I will try that ... ^_^ if I can get a pick of the critters I will post it ... I cut off all the dead leaves and things that didn't look to happy ... so I will do the spraying... and I will invest in some herbs and other things BEFORE I do the planting ^_^

 

[The Rubber Kitty]

[QUOTE="ClissAT,


As far as suitable herbs are concerned, it is far better to have mature herbs already growing when you put in your veg. Mature herbs have a full potential of combatants available to protect the young vegie plants. Planting young herbs won't help the existing mature vegie plants which already have put out a registration to alert the critters.[/QUOTE]

So I have some Lavendar growing with some of them... Parsley, Basil, rosemary ... dill? just smelly stuff?

 

[The Rubber Kitty]

]@ClissAT

I Got pics of the critters

IMG20200106171133

• The Rubber Kitty
• Jan 9, 2020

Close up of yellow pest

IMG20200106171125

• The Rubber Kitty
• Jan 9, 2020

More of them on my kipflers

 

[Mark]

Yes, this is the larvae of the 26-28 spotted ladybug and it's no doubt a pest.

Pyrethrum is considered organic and although I'm loathed to use it sometimes it can be a quick and effective option to control big infestations like yours when picking them off by hand isn't practical. Pyrethrum used as directed will work. Just be aware it will kill bees so don't spray over flowering plants.

However, if you are local (SEQ area) it might be prudent to simply cut the plants back altogether because if the leaf damage is the same all over the plant as in the pics then they are too damaged anyway and only new growth will help.

Also, in this part of the world, we are not in potato season. In the subtropics, potatoes are best planted at the end of summer through to the beginning of spring. Potatoes grown through a subtropical summer will grow poorly and thus attract pest and disease.

If your crop has been growing for a few months already it might simply be time to dig them up...

 

[The Rubber Kitty]

Yes, this is the larvae of the 26-28 spotted ladybug and it's no doubt a pest.

If your crop has been growing for a few months already it might simply be time to dig them up...

Awesome ... I will do that ^_^ and yeah they have been growing for a few months... for lack of what to do I just cut it all back... and did the spraying with the soapy mixtures as above suggested...

As I am trying to undergrow and things ... i am not sure about pyrethrum... unless I can grow them with? I will make a note to plant spuds at the end of summer.

Thanks @Mark

 

[The Rubber Kitty]

@Mark yeah I am in SEQ ... down Logan way ... I live where they have reclaimed swamp... so the soil is brown clay type ... I have my garden in drums at the moment, but am looking for raised beds for later when I have finished building another shed for the Man Cave ^_^