В этом сквере весной всегда много цветов, а на клумбе у входа особенно красивые тюльпаны.

Because в этом сквере means in this small park / square, describing location, not movement.

Russian uses:

• в + accusative for movement into something: в этот сквер = into this square
• в + prepositional for being in a place: в этом сквере = in this square

Here the sentence describes where the flowers are, so Russian uses the prepositional case:

• этот сквер → в этом сквере

Весной is the instrumental singular of весна.

In Russian, some seasons and times of day can be used in the instrumental case to mean during... or in...:

• весной = in spring
• летом = in summer
• осенью = in autumn
• зимой = in winter

So весной here means in spring.

A learner often expects в весне or something with в, but Russian normally just says весной for this time expression.

Russian often leaves out to be in the present tense.

So instead of saying something like:

• В этом сквере весной всегда есть много цветов

Russian very naturally says:

• В этом сквере весной всегда много цветов

Both can be understood, but omitting есть is very common, especially in descriptive sentences.

Literally, the structure is closer to:

• In this square in spring always many flowers

This is normal Russian.

After много (many / a lot of), Russian uses the genitive plural.

So:

• цветы = nominative plural, the basic dictionary plural
• цветов = genitive plural

That is why Russian says:

• много цветов = many flowers

This is a very important pattern:

• много людей = many people
• много книг = many books
• много домов = many houses

Because they play different grammatical roles.

In много цветов, the noun follows много, and много requires the genitive plural:

• цветов

But in особенно красивые тюльпаны, тюльпаны is the main noun of the phrase, so it stays in the nominative plural:

• красивые тюльпаны = beautiful tulips

So:

• много цветов = quantity structure → genitive plural
• красивые тюльпаны = ordinary noun phrase → nominative plural

Russian often uses different prepositions with places in ways that do not always match English exactly.

Here:

• в сквере = in the square / park
• на клумбе = on the flowerbed

A клумба is thought of as a planted bed or surface area, so на is natural.

Compare:

• в парке = in the park
• в саду = in the garden
• на клумбе = on the flowerbed
• на площади = in the square / on the square

You often just have to learn which preposition goes with which noun.

Клумбе is prepositional singular.

It comes from:

• клумба = flowerbed

After на when talking about location, Russian uses the prepositional case:

• на клумбе = on the flowerbed

So the pattern is:

• клумба → на клумбе

У here means by / near / at.

So:

• у входа = by the entrance / near the entrance

After у, Russian uses the genitive case:

• вход → входа

This is a very common pattern:

• у дома = by the house
• у окна = by the window
• у метро = by the metro station
• у входа = by the entrance

Особенно means especially and it usually goes before the word or phrase it emphasizes.

Here it emphasizes красивые тюльпаны:

• особенно красивые тюльпаны = especially beautiful tulips

It can often move around, but this position is very natural. The sentence is contrasting two ideas:

• there are many flowers in general
• but the tulips by the entrance are especially beautiful

So особенно naturally comes right before the adjective phrase.

Because this phrase is not controlled by много or another word that would require genitive.

It is just a normal adjective + noun phrase in the nominative plural:

• красивые тюльпаны = beautiful tulips

The adjective agrees with the noun:

• тюльпаны = nominative plural
• красивые = nominative plural

If it were after много, then both would change:

• много красивых тюльпанов

That contrast is very useful:

• красивые тюльпаны = beautiful tulips
• много красивых тюльпанов = many beautiful tulips

Not exactly. А can mean and, but it often signals a contrast or a shift of focus.

In this sentence:

• В этом сквере весной всегда много цветов, а на клумбе у входа особенно красивые тюльпаны.

The idea is:

• there are many flowers in the square in general,
• and / while / but on the flowerbed by the entrance, the tulips are especially beautiful.

So а is better understood as something like:

• and as for...
• while...
• but...

It connects the two parts while also contrasting them a little.

Yes. Russian word order is flexible, although the original version sounds very natural.

Original:

• В этом сквере весной всегда много цветов, а на клумбе у входа особенно красивые тюльпаны.

Possible variations:

• Весной в этом сквере всегда много цветов...
• На клумбе у входа особенно красивые тюльпаны.
• Особенно красивые тюльпаны — на клумбе у входа.

Changing word order usually changes focus or emphasis, not the basic meaning.

The original order sounds smooth and neutral:

1. place
2. time
3. general statement
4. contrast
5. more specific location
6. highlighted detail

Not exactly.

Сквер usually means a small public garden, small square, or landscaped green area in a town or city.

Парк is usually a park, often larger.

So:

• сквер = smaller, often urban, like a landscaped square
• парк = park, usually larger

In this sentence, сквер suggests a smaller city green space with paths, benches, flowerbeds, and planted areas.

Yes. This is completely normal in Russian.

Both parts are descriptive and use an implied present-tense there is / are structure:

• В этом сквере весной всегда много цветов
• а на клумбе у входа особенно красивые тюльпаны

Russian often builds sentences this way when describing what exists somewhere.

In natural English, you might translate more fully:

• There are always many flowers in this square in spring, and the tulips in the flowerbed by the entrance are especially beautiful.

But in Russian, no present-tense verb is needed.