The spell Goodberry produces ten berries that heal one hit-point each. It has a few other uses in terms of nutrition. Have some RAW berries:
Up to ten berries appear in your hand and are infused with magic for the duration. A creature can use its action to eat one berry. Eating a berry restores 1 hit point, and the berry provides enough nourishment to sustain a creature for one day. The berries lose their potency if they have not been consumed within 24 hours of the casting of this spell.
They appear ‘in your hand’, like a warlock’s pact-weapon such as a two-handed battle-axe would. They can be consumed at a rate of one per six seconds. Possibly incredibly small, this berry will only fit in a mouth at a rate of one per six seconds – Lord Crawford Rules.
These berries can be of any genre, make &/or style – thus one could have ten different types berries. Also interesting: a pumpkin is technically a berry, the maximum size of such a fruit can be rather large – heavier than a car. Still, this is only good for ONE (1) meal. The rules also specify that you can eat that thing under six seconds. If you can make pumpkin pie you will win the contest and gain one hit point in the process – assuming such a pie is made wafer thin.
Still, nothing in the rules about serving these fruits with a trebuchet. You will want to chill them first because, as the Klingons say: revenge is a dish best served cold. Giants with the optional Druid caster-upgrade would have 40 shots on hand – so handy.
Question / Repeat:
Can one use the Goodberry spell as a weapon?