Pests on my Rhubarb

[Monkey_honk]

Hello, I am a newbie to all of this!! Found these guys on my rhubarb today. Not too happy about them! Can anyone tell me what they are please and the best way to get rid of them. Been here about a week (I've been awa) and pretty sure they aren't doing it any good.

Thanks
Amy

[rustylady]

Ah, slightly clearer picture on this thread. Look like aphids. Squish them with your fingers.

[Monkey_honk]

Thanks Rusty Lady. Is it common to have ants with aphids?

[Monkey_honk]

Also, there seems to be a whole load of them. Can I not spray them with pest killer? Don't want to lose my Rhubarb

[FB.]

Also, there seems to be a whole load of them. Can I not spray them with pest killer? Don't want to lose my Rhubarb

No need to "nuke" for just aphids - and if you do nuke 'em you'll risk collateral damage to other beneficial insects (bees, ladybirds, hoverflies to name just a few).

The biggest problem for my rhubarb is snails and slugs eating the leaves rather than aphids just sucking some sap.
But neither snails nor aphids nor my modest stem-pulling in spring slow down my rhubarb (Timperly Early).
The biggest threats to anyone's rhubarb is being greedy and pulling too many stems (I never take more than half the stems, and don't take any stems from about this time of year), especially from young plants, and not giving the plant enough nutrients to allow it to replace the stems which have been pulled.

If rhubarb is adequately fed (compost or manure - but not right up to the crown or the crown will rot) and given a little water during dry spells, plus any stem-pulling done sensibly and not greedily, it should produce well and be barely affected by pests or diseases.

[Monkey_honk]

Thanks FB. I have only taken 3 stems from the plant this year, and won't take anymore now, in the hope that it grows larger for next year.

Ok, I won't nuke it, just so disheartening hope it survives.

[FB.]

just so disheartening hope it survives.

It'll only die from an aphid attack if it is already weakened from one or more of the following:

1. Lack of nutrients/poor soil.
2. Lack of water (it's fairly tolerant of dry spells, but I had to give mine a bit of water a couple of days ago - half the leaves had gone yellow and wilted)
3. Pulling too many stems - especially on young plants - because pulling stems or removing leaves will weaken any plant, not just rhubarb.
4. It is suffering from crown rot - either from burying the crown under damp compost/manure or from being in very heavy/saturated/flooded soil, or because it brought disease with it from the nursery.

I suspect there are plenty of people here who would chop a piece off their rhubarb for you during the winter - why not fill in your approximate location in your profile?
Knowing where someone lives helps a lot if you ask for advice because the UK has many different micro-climates with their unique challenges.

[Monkey_honk]

I shall do that I'm all new to this growing stuff lark. Really enjoying it however. Nice to meet people and learn from them shall apologise for the stupid questions in advance.

[veggiechicken]

I don't know whether its the camera lighting but the leaf they're on looks yellow compared to the rest - is it an old leaf? If the aphids are only on that leaf I'd be tempted to pull it off and get rid of it (bucket of water?)
BTW, Welcome to the Forum and, as FB says, if you could add your location to your profile it would be very helpful

[Two_Sheds]

Is it common to have ants with aphids?

They are the best of friends
Herding Aphids: How 'Farmer' Ants Keep Control Of Their Food

Can I not spray them with pest killer?

Unfortunately, pest spray isn't selective: it doesn't just kill the ugly insects, it's also toxic to others, like bees (you might have heard that bee populations have crashed). Even if you don't "zap" a bee with it, the spray goes into the atmosphere

Our insects, and the birds & other creatures that feed on them, are dying out ... because people would rather use a sprayer than their fingers & brains





Sorry, Monkey. Welcome aboard, nice to meet you. Hope you stick around, I hope your rhubarb survives (it will: it's as tough as old boots)

[FB.]

Unfortunately, pest spray isn't selective: it doesn't just kill the ugly insects, it's also toxic to others, like bees (you might have heard that bee populations have crashed). Even if you don't "zap" a bee with it, the spray goes into the atmosphere

The recommendations for spraying fruit trees - such as in the widely-owned "Fruit Expert" <Hessayon> (a book which sounds more impressive than it actually is) - suggest spraying fruit trees at petal fall. However, I have regularly seen bees landing on petal-less or near-petal-less flowers; not to mention that a fruit tree can have a few late-opening flowers after petal fall which attract bees.
Once a plant has been sprayed, any insect which so much as touches the plant is at risk of death by contact with insecticide - even if a bee just lands on a leaf for a rest in the sun before continuing its journey.

[Monkey_honk]

Would pulling off the leaf stop the stem from growing? There seem to be more today than yesterday, after sitting for ages pulling the buggers off! Nope not an old leaf Veggie. Plant is relatively new to me. Purchased from a garden centre recently. All the leave are varying shades of green, no yellow to speak of

I shall persevere with it. I'm really into growing my fruit, even though I eat little of it. I want to show my son that you don't just pick it from the shelves in the supermarket. He enjoys being in the garden and helping with the watering. He is Autistic so this is something new for him, and were learning together.

Thanks for all being so lovely and helping me.

[FB.]

Would pulling off the leaf stop the stem from growing? There seem to be more today than yesterday, after sitting for ages pulling the buggers off!

Aphid numbers can build rapidly. Hoverfly and ladybird larvae usually arrive after a couple of weeks and eat the aphids, leaving shrivelled black aphid skins behind.

Pulling the leaf off will do more damage than leaving it* because the plant will lose all the light-gathering power of the leaf, rather than losing just a part of the leaf output to the cluster of aphids sucking from just a few of the veins.
* An argument could be made that by pulling the leaf it would stop the spread, although aphids may already have wandered to other leaves (or been transported by ants, or will fly-in again from nearby plants) where they will start new colonies.

If it really worries you (although it doesn't worry me) you could use a water pistol or hose to blast them off.

At least one of my rhubarb plants has hundreds, maybe thousands, of aphids on it at the moment, but I don't intend to do anything about it.
Picture below, taken a short while ago, showing heavy aphid infestation (including some ants) on a young leaf of one of my Timperly Early.

-

[Monkey_honk]

Oh right :/ so I have a few questions FB (prob stupid ones) why won't you remove them? Are they not going to kill the plant or weaken it? And what's the deal with the ants and the aphids?

[Monkey_honk]

P.s. shall attack with the hose tonight.