Is it standard practice to fertilise seedlings? I have 2year old seedlings that are still tiny 6” plants, would it be sensible to give them a little liquid seaweed fertiliser, or best not?
I don't fertilize any seedlings R. I did try it many years ago and it killed them all. So IMO I would say no leave them alone. Ps I hope your enjoying that strange yellow circle in the sky this weekend.....
Thanks - I did wonder whether that would be the outcome! Yes it’s been lovely today, it wasn’t forecast for here, was only supposed to be warm!
Ordinarily I would agree not to feed seedlings, but if they are 2 years old and in the same soil then they probably need a little something. If they've been repotted into fresh soil then best not to feed them, but in depleted soil they will need feeding. There is no way of knowing if some of the micro or macro nutrients have completely leached out of the pot after 2 years, and if any of them are completely absent then the plant will fail. I would recommend no more than quarter strength liquid feed for seedlings, but seaweed is pretty mild stuff so maybe up to half strength with that?
Also, if you water the seedlings always with rainwater (more or less pure water when it falls from the sky) then the pots will leach minerals quicker than if you water them with tapwater which generally has a background amount of minerals. Our local water company, Anglian Water provide a very comprehensive postcode based water report, worth checking out if you are curious: https://waterquality.anglianwater.com/map.aspx. I usually water my maples with rainwater, so have to be aware of the seedlings with small soil volumes that can leach minerals relatively quickly. I will give seedlings and other small pots an occasional watering with tapwater because I know that my tapwater has a little bit of everything needed for plant growth.
This makes a lot of sense..I have 4year seedlings that look healthy with 1cm thick trunks but are quite small, like a foot tall. I have only ever watered seedlings with rain water so what you have explained adds up. Thank you, much appreciated.
When I first put my seedlings in pots, from a grow box or the like, I never add fertilizer : the substrate is good enough. When I repot in larger pots, after 2,3 - or more years, I add slow-release fertilizer (osmocote) that take 6 months to be deleted.
Yes I do like Alain. With the exception of dissectum seedlings, which /hate/ fertilizer. But if you give them nothing after 2 years, they take so long to build up roots that any stress can kill them off. Also, remember people who are growing rootstock (often seed from a very easy to germinate plant, like Sango kaku), need to get usable stock in no more than 2 years. (3 if they're really reputable). So they definitely fertilize. Of course now there's a lot of pegged layer rootstock coming out of Holland, which allows you to start with a larger diameter; but has it's own problems (i.e. it's a rooted cutting, and we all know about those). -E
