Fertilizer

[nurvbonsai]

Hi all,

I was wondering after receiving my tree talk email from my local club that this month I should start to ease up on fertilizing. I’ve been using primarily the Fox Farm brand this season and every other watering (2 days) but this week have started to not. So what’s the move here?

Thanks.

 

[badatusernames]

No idea what’s in the fox farm stuff but every two days sounds aggressive to me

Depends on where you’re at in development

I use:

Osmocote: early / young stuff
Gro-power tabs: mid-development
Bio gold: more mature trees in pots

Plus a weekly dose of fish and seaweed liquid when I remember, maybe iron chelate if they need it (if ume leaves are going a bit yellow mainly)

Osmocote and gro-power last awhile so I just add more after it dissolves

Biogold I change out once a month

 

[nurvbonsai]

I’m in early development still. A lot of my trees and responses to them were recommended with Oscomote, liquid fert such as fox farm.

 

[Shibui]

There are lots of myths about fertiliser. I've seen lots of crap published in club newsletters, usually just regurgitated from past editions or old manual so don't take everything you read as gospel.
Traditional wisdom is no fertiliser through winter but, through trials, we have discovered that fertilising evergreen trees right through our (mild) winter boosts Spring growth.
Traditional wisdom is that Fall fert produces soft growth that won't survive winter. That does not seem to happen in practice (here). Maybe applicable to much colder areas?
Traditional wisdom is reduced N and increased K for winter hardiness. That seems to have been disproved by hort science but I still see it in club newsletters and resources.
Many of us use controlled release fert like Osmocote. That continues to release fertiliser whenever the soil is damp. It does not suddenly stop releasing before winter but the trees seem to manage to stay alive even though they are receiving fert right through to leaf drop (and beyond)

Deciduous trees cannot use nutrients when they have no leaves so definitely stop fertilising at or before leaf drop but stopping much earlier will leave your trees short of nutrients to store for winter. If they have to reach into stores to survive until leaf fall that will leave them short in Spring. Maybe that's Ok for developed trees where you want restricted growth but will slow growth and development in younger trees.
Exact timing will depend what form of fert you are using. Liquid fert is quick acting and quickly gone so can be continued longer than organic which releases slowly over weeks and months.
My advice is to continue to fertilise through to Fall, though you might like to reduce rates and frequency through late Summer and Fall.

 

[leatherback]

that this month I should start to ease up on fertilizing

The way I look at it, from a biological point of view..
Trees turn yellow red, orange whatsoever in fall. This is becuase the tree is breaking down the leaves active components, starting with chlorophy. They try to pull in as many nutrients from the leaf before it drops in fall. Next to this, in fall you get an enormous mineralisation in the soil (note the mushrooms popping up everywhere). So fall is a period of enormous movement of nutrients in the plant. Why would we not use this natural cycle and provide the tree what it naturally is looking for during that phase?

I have not yet noticed a massive push of growth when fertilizing.

For "needled evergreens" where needle length is affected by available nutrients I have been recommended to beef up fertilizer in fall, when the needles are not growing, and hold off on fertilizing in spring untill the first needles have extended, as this reduces branch thickerning and needle length..

Go figure. Nothing it true. It all depends.

 

[Bonsai Nut]

I primarily use time-release organic tabs, and (believe it or not) Miracle Grow water soluble. I replace the tabs when they disappear, and fertilize with the Miracle Grow every two weeks, and stop fertilizing entirely when trees drop their leaves.

[EDIT] I should have probably added - I stop fertilizing my conifers with the first frost, which for us is typically in early to mid December. I start fertilizing in the spring when I see the first hints of growth / bud expansion [/EDIT]

 

[Dav4]

I fertilize regularly throughout the growing season and into the fall, and I use the same feed- organic solids on the soil surface and mainly fish emulsion with some dyna-gro every 7-10 days. Deciduous trees get their last application when the leaves are beginning to fall and the conifers get theirs when night time temps are routinely dropping into the mid to low 30's F and I'm preparing to winterize them.

 

[Glaucus]

Now is the best time to fertilize. Just not too much.