At 250% productivity still only 1 cart, this often results in insufficient dung
conflate with (e.g.) fur dealer at 385% which has spawned 4 carts
you seem to need to define the fertiliser works using the regular template used for other factories (i suppose you had some reason not to, but now you need to fix the resultant downsides)

@hundreAd1800
In update 14.1, they reduced the production timer from 5min to 30sec (a factor of 10), and increased internal storage from 1 to 5. It looks like they should have increased the number of carts as well

@Ubi-Milky
i thought the <Template> was the problem so i modded it to Mall (which has input+output+buff), and now it can even use electricity... but STILL only a single cart at 350% productivity
maybe the problem is somewhere in the game logic rather than the xml?
(it's not because it's a hacienda building, i've electrified a hacienda distillery, which promply got multiple carts -- 3 at 250%, as expected per normal game behavior)




EDIT:
setting <TransporterCountMax> under <LogisticNode> will result in more carts
however the downside is that the number is fixed (the max is apparently also MIN) and not variable as per normal game rules (every +100% productivity = +1 cart)
i cannot find anywhere in the xml that restricts the max to 1, it has <LogisticNode />, so no idea how/why this is caused

@Ubi-Chiral

team confirmed that this is working as intended as all production buildings in the New World have only 1 cart

your team are either playing another game or else smoking way too much nw herbs! (not quite sure how many carts their herb garden got...)
no wonder there is a new icon_bonusgood_cigarettes:

</sarcasm>

seriously now:
as per game rules, +100% productivity gives +1 cart (ScaleMaxTransportersWithMaxProductivity)
this of course applies to the new world
the hacienda fertilizer works is the EXCEPTION

here is the HACIENDA rum distillery happily using multiple carts:


and here are some other new world buildings, also using multiple carts:



and dlc12 new buildings, also with multiple carts:



i realize that in propertiespc.xml there is

       <LogisticNode>
         <TransporterCountMax>1</TransporterCountMax>

however everything ELSE blithely ignores that (never managed to find out where this is overridden but nm)
(the above applies to buildings in all regions, not only nw)

and indeed, giving the poor fertilizer works

<TransporterCountMax>4</TransporterCountMax>

fixes this problem, cart usage will scale with productivity as normal (max 250% with 3 +50% items, or 350% if you ever deign for it to use electricity, so 4 carts)

EDIT:
just for reference, here are the buildings that have <TransporterCountMax>1</TransporterCountMax>:

//Values[LogisticNode/TransporterCountMax=1]/Standard/Name/text()

heater_arctic
electricity_03 (Gas Power Plant)
electricity_04 Fuel Power

for whatever reason, electricity_02 (Oil Power Plant) does NOT have this limitation