Do land circle druids use spell slots when they cast their land circle spells

Question

In 5e D&D, do Land Circle Druids use spell slots for their Land Circle spells? For example, a second level Druid gets 2 cantrips - no spell slots needed - and 3 1st level spell slots. So, he can basically cast 3 spells at 1st level and his cantrips. If that druid chooses to go Land Circle, such as Swamp Circle, he adds 2 new Land Circle spells, always prepared, to his collection - Darkness, and Acid Arrow, both not cantrips.

My issue is, if he's required to use spell slots to cast those Land Circle spells, then they aren't that great. He could do as well with plain old Druid spells, things like Fog Cloud, Ice Knife, and Earth Tremor. So if he has to use spell slots for Circle Spells, why not choose a different circle? He does get a couple other things as, for example, Swamp Circle, like Land Stride, but that's only useful in a very, very, very small percentage of situations. So I'm wondering if I'm reading Land Circle Druids incorrectly. It says their Land Circle spells are always prepared, but that's not a big deal for a Druid, is it?

Do they have to use their limited spell slots to cast their Land Circle spells?

Answer 1

Yes, Circle spells (of 1st level and higher) require spell slots.

For druids (and other spellcasters who prepare spells), the benefit of extra spells is that they are always prepared, in addition to the number of spells they can prepare after a long rest.

Once you gain access to a circle spell, you always have it prepared, and it doesn’t count against the number of spells you can prepare each day. If you gain access to a spell that doesn’t appear on the druid spell list, the spell is nonetheless a druid spell for you.

Normally, a druid prepares a number of spells equal to their druid level + their Wisdom modifier. Circle Spells are always prepared in addition to this number. So even if a Circle Spell is already on the druid spell list, the Circle of the Land druid effectively has more spells prepared than other druids.

These spells otherwise follow the rules for a druid's spellcasting, which typically means expending a spell slot to cast a druid spell.

To cast one of these druid spells, you must expend a slot of the spell’s level or higher. You regain all expended spell slots when you finish a long rest.

Because druids have Ritual Casting, they can cast any of these spells as a ritual if it has the "ritual" tag. Otherwise it requires an appropriate spell slot to cast.

Answer 2

A spell gained from a Circle requires a spell slot to cast, but it counts as a Druid spell and is always prepared

The Circle Spells feature is similar for each subclass of Druid and below I will quote the one from the Circle of the Land Druid

Your mystical connection to the land infuses you with the ability to cast certain spells. At 3rd, 5th, 7th, and 9th level you gain access to circle spells connected to the land where you became a druid. Choose that land - arctic, coast, desert, forest, grassland, mountain, swamp, or Underdark - and consult the associated list of spells.

Once you gain access to a circle spell, you always have it prepared, and it doesn't count against the number of spells you can prepare each day. If you gain access to a spell that doesn't appear on the druid spell list, the spell is nonetheless a druid spell for you.

This shows that when you "gain" a Circle spell what happens is that you will always have it prepared (if you have a spell slot available, you can cast it), and that this does not count against your usual limit on the number of spells you can prepare after a long rest.

There is another unusual advantage covered by the last sentence of the desciption; even if the spell isn't normally a Druid spell it counts as one for you (this puts it on equal footing with your other Druid spells). This allows you to add your Wisdom to any spell save DC or attack modifier, lets you cast it as a ritual (if possible), lets you use a druidic focus with the spell and finally it will benefit from the features Beast Spells and Archdruid.
The reason it allows for these things is because each of these only apply to Druid spells, not just any spells you cast.

Answer 3

Circle spells require spell slots

First lets start by looking at the rule for Circle Spells (emphasis mine):

Your mystical connection to the land infuses you with the ability to cast certain spells. At 3rd, 5th, 7th, and 9th level you gain access to circle spells connected to the land where you became a druid. [...]

Once you gain access to a circle spell, you always have it prepared, and it doesn’t count against the number of spells you can prepare each day. If you gain access to a spell that doesn’t appear on the druid spell list, the spell is nonetheless a druid spell for you.

Nothing in this ability modifies how you cast spells, only granting a list of prepared spells that still use spell slots. However, it has a few good benefits you may have overlooked.

Additional prepared spells increases flexibility

By default druid's prepare spells according to the following rule:

You prepare the list of druid spells that are available for you to cast, choosing from the druid spell list. When you do so, choose a number of druid spells equal to your Wisdom modifier + your druid level (minimum of one spell).

Particularly at early levels this small number of options can be quite limiting. Do you take that extra healing spell or an offensive one? By giving additional spells that do not count against this limit Circle Spells increases your flexibility and the options available to you when preparing spells.

Access to powerful spells not on the druid list

I've talking in another answer about how the druid spell list isn't really that powerful. By default they have less powerful offensive options available than wizard/sorcerers, weaker buffs than cleric and less manipulation than bards. Their spell list lets them do a bit of everything without being great at anything.

Circle Spells help address this by giving access to some great spells that are otherwise unavailable to druids. Even better, these spells count as druid spells for you, so you can use wisdom as your spellcasting ability.

Why not choose a different circle?

Circle of the Land is for druids who want to be pure spellcasters. They have access to more and more powerful magic than the other circle and don't have to waste their time turning into fluffy critters (circle of the moon) to be dangerous. In addition to the benefits above they have a couple of features that make them better spellcasters than other druids.

The bonus cantrip is nice, it means you don't have to choose between a ranged damage, melee damage and thematic cantrips, you can have them all! Unfortunately druid cantrips are fairly weak in general compared to other classes, but this is still better (for spellcasting) than anything other druids get.

The bigger benefit is Natural Recovery:

Starting at 2nd level, you can regain some of your magical energy by sitting in meditation and communing with nature. During a short rest, you choose expended spell slots to recover. The spell slots can have a combined level that is equal to or less than half your druid level (rounded up), and none of the slots can be 6th level or higher. You can’t use this feature again until you finish a long rest.

This feature gives a big boost to the number of spells you can cast per day. When combined with the Circle Spells this question is about it is the main reason Circle of the Land is the go to for pure spellcasting druids.