Summoning a creature such as Vegetable Lamb, it will daily grow a 1d4 flowers that have the ability to heal creatures. Are they intended to be summoned with such flowers, or would you have to have the creature for a day, i.e. 1 minute won't cut it. and that ability is not intended to be relevant when in play via summoning.
I know that summoned creatures can't summon other creatures, and can't cast magic of any magic of equal level that created it, and are basically prevented from using any reactions. (which may drastically affect usability of certain creatures)
A second level spell a second level spell giving you 1d4 x (1d6+4) healing is not super extraordinary. A second level heal spell cast 3 actions could easily out do it, so it 'might not' be too good to be true. However, if the number of flowers rolled is high, the single target healing capability would see pretty good as a secondary effect. And perhaps rather than comparing it to a second level spell, we should compare it to first level spells when trying to decide if it is too good or not.
I would presume the vegetables picked off such a creature would vanish if they are not consumed prior to the Summon being dismissed, so you would have to pick them and use them in the span of up to a minute of sustaining a summon. A minute compared to a day is downright nothing, so I don't think you can use it to stock up on consumables to use through the day.
When first reading, I assumed they were intended to come with the summoned creature, but I began to wonder if it might be too good to be true.
For balance comparison: With a Rank 2 Summon Lesser Servitor spell you should be able to summon a Cassisian, which can cast a Rank 1 Heal spell. The Summoned trait would cause a Rank 1 Summon Lesser Servitor spell to run into problems with a creature casting a Rank 1 Heal spell. however, a Rank 1 summon spell wouldn't be strong enough to summon the Cassisian to begin with.
For rules: The Summoned trait does say that the summoned creature is able to use all of its standard abilities for a creature of its type. No restriction is listed other than for spells.
So I would allow the Vegetable Lamb to have its 1d4 Nature's Bounty flowers. Nature's Bounty is one of its standard abilities.
Yes, it has the flowers since it's not an action or Exploration activity. It has 1d4 each day, and since each casting manifests a new creature, they should be available for each lamb.
Since each eating takes an action (and typically a free hand), eating in combat isn't that great. At my table I'd also presume and rule that the flowers disappear when the lamb does, as the flowers are effectively a piece of the lamb. If the lamb created them anew, that'd be different.
And as for balance requiring overruling this, I see no issues with balance. It might allow a party to disperse healing more efficiently, but it's more of a gamble than Heal, and more an out-of-combat tactic competing with Medicine, Lay On Hands, etc. which are superior and endless resources.
I would say the "flowers disappear when the creature does" is a knock-on effect of the part of the Summoned rule that " A summoned creature can't summon other creatures, create things of value, or cast spells that require a cost."
Since there's nothing about the flowers that suggest they expire in a day for a non-summoned one (indeed, the examples are things like "broccoli" which can last for weeks) they are arguably "a thing of value" if they don't expire when the creature disappears.
The way I read it, the flowers are parts of the lamb that can be picked off, lamb-bits that regrow. Thus they disappear when the rest of the body does. Nothing punitive, simple interpretation. If the lamb generated them separately, especially out of non-summoned matter, then I'd agree the flowers should outlast the creature poofing out of existence.
Don't items that summoned creatures come equipped with also disappear whether or not the creature's holding them?