I posted earlier about aphids, and I’m noticing that I had aphids in the soil that my seedlings who had just started with about a half an inch of taproot from the paper towel method.
I would put these seeds with their tap root into the soil, and noticed that some of them just didn’t grow, I mean break the soil. I would dig around and find the seed had barely cracked open, but the taproot was gone and only a little bit of it was sticking out from the seed’s shell.
I’m trying to revive a seed that I found in this condition by putting it back in water, hoping that it will sprout another, or the same, taproot.
My question is, what pests go after the taproots of new seedlings?
I have seen aphids in my grow tent, the white ones that are super small, and in the case above, I saw them in the actual soil, on the top, in the red cup that the seed was trying to sprout from.
The soil is Fox farm happy frog, and it was sitting around for a couple of weeks. I suppose they all ship with pests, so I have no qualm there.
Has anyone else ever seen this happen to their new seeds?
Its hard to say without a little more info. Did the soil go dry when you transplanted the seed. Or did you happen to place it in dry soil then water it in. Because dry soil has raw nutrient salts that have to be soaked first or it will cause the roots to dry out and die or wreak havoc on a plant.
Also im not sure it was aphids you have as much as fungus gnats which are very common with potting soils. And the larve do feed off roots.
If you saw aphids in the soil, they are probably root aphids. One other thing that can cause seedling roots to fail would be over watering. Really freshly sprouted seedlings only need a couple of tablespoons of water each day in a circle around their ‘drip line’ meaning water outside of where the water would drip off the leaves if it were to get rained on.
Put sand on top of the soil, wrap landscape fabric around the stem and on top of the soil, or mix 2 Tablespoons of neem oil in a gallon of water and drench the roots with it. You can put yellow sticky traps out to see if you can catch one and look at it.
The only critters I have seen on the soil within the red cups that has eaten the roots and even the seeds out of the shells, are these little white guys, and I have a picture or two in the thread showing how big they are. They’re not really fast movers, but they move fast enough that you can spot them on the leaves.
I am so far from being a bug expert, I posted them thinking that they were aphids just by the description I’ve read, not because of any pictures. It’s weird how many websites just describe them instead of just showing you a picture of what they look like!
Nothing I’ve seen has wings of any kind, but I might be looking at them in a much younger stage where they don’t have them. I have also only noticed them across the tops of the leaves and running across the soil in the cups.
I’m beginning to think that because I did not drench them in water before putting seeds in them, in other words using them dry, this may be why I’ve had so many failed seedlings where everything but the shell has disappeared.
I probably haven’t had any bad seeds above the usual average, blaming something else for the seeds not sprouting after cracking open in a shot glass and towel. It now looks like, and it makes more sense that, I’ve been letting critters chow down on my little beans…
This is a picture with one of the little white guys on one of the leaves. If this isn’t an aphid, can somebody tell me what it might be?
From what you are describing, it sounds to me that you have root aphids.
This is an emergency situation and you need to act quickly before this problem gets really out of hand. Root aphids can double their population every 1.5-2 days, and reproduce asexually by cloning themselves and giving live birth. They are also able to live for quite some time without food, so simply clearing a tent out and reloading it isn’t necessarily going to solve any issues.
As they age, or you introduce stress to the population, they will develop wings and turn into flyers. The stress response to start flying is to ensure survival of the population.
In order to get a good handle on root aphids IME is a multi-functional attack. You can line your plants pots with yellow sticky cards to help prevent them from going from pot to pot. It will also be wise to have additional sticky cards hanging in the canopy and around your tent for when they start flying. My next suggestion would be to do some root drenches with some Azadirachtin (Neem Oil) paired some a product that has Beauveria Bassiana (BotaniGard 22WP). You can also use these same chemicals as a foliar application that will help eliminate any flyers. From my experience, this is a pest that you can get control of and eliminate in a small sized grow, but it does require some persistence.
It would also be wise to add an additional chemical that can be used to alternate sprays. Suffoil-X or Athena IPM are a couple examples that I would consider. This will be to ensure you’re not spraying the same chemicals over and over and letting the bugs develop a resistance to your pesticides.
You can also introduce beneficial insects (Atheta/Rove Beetle) that are natural predators of root aphids.
As soon as I noticed them on the leaves, it was probably two or three days until I brought the whole thing outside. I haven’t seen anything in the tent, as far as the other ones were concerned, and it was only a 2x2. It’s sisters already gone into the outside and one into another tent. They haven’t shown any signs of the little critters, any of them, so fingers crossed.
Thanks for the good info. I’m sure it’ll be really useful for future readers.
I would still be very cautious if you are growing in the same space the aphids were present in. Since they reproduce asexually, and are able to increase their populations very quickly and efficiently, all it takes is a couple of them hiding in your space to repopulate.