Сколько ни поливай цветы, без солнца роза и тюльпан растут медленнее.

It means something like No matter how much you water the flowers or However much you water the flowers.

This is a common Russian pattern:

• сколько ни ...
• как ни ...
• кто ни ...
• где ни ...

These often mean no matter how..., however..., whoever..., wherever..., etc.

So here:

• Сколько ни поливай цветы... = No matter how much/how often you water the flowers...

The second part gives the result:

• без солнца роза и тюльпан растут медленнее = without sun, a rose and a tulip grow more slowly

So the full idea is: watering alone is not enough.

Because this is the fixed concessive pattern сколько ни ..., meaning no matter how much or however much.

Compare:

• не usually negates something directly.
• ни often appears in set expressions that strengthen the idea of it doesn’t matter how / no matter how.

So:

• Сколько ни поливай... = No matter how much you water...

Using не here would sound wrong in standard Russian for this meaning.

Formally, поливай is the imperative of поливать (to water, imperfective). But in this sentence, it is not a real command.

In the pattern сколько ни + imperative, Russian often uses the imperative to express a general repeated action:

• Сколько ни старайся... = No matter how hard you try...
• Как ни смотри... = However you look at it...
• Сколько ни поливай... = No matter how much you water...

So here, the imperative works more like a general you do X as much as you want / even if you keep doing X.

Because the sentence talks about an ongoing, repeated, or unlimited action: watering again and again.

• поливать = imperfective, focusing on process/repetition
• полить = perfective, focusing on a completed act

In Сколько ни поливай..., the meaning is however much you keep watering or no matter how often you water, so imperfective is the natural choice.

A perfective imperative here would not fit the general, repeated sense nearly as well.

Цветы is the accusative plural of цветы / цветок in meaning, because it is the direct object of поливай:

• поливать что? → цветы

For inanimate plural nouns, the accusative usually looks the same as the nominative:

• nominative plural: цветы
• accusative plural: цветы

So the form stays цветы.

Because the preposition без (without) requires the genitive case.

So:

• солнце = nominative
• солнца = genitive

Examples:

• без воды = without water
• без света = without light
• без солнца = without sun/sunlight

That is why the sentence has без солнца.

Russian often uses the singular to speak about things in a general, class-like way, especially when naming types or species.

So:

• роза и тюльпан растут медленнее can mean a rose and a tulip grow more slowly, or more naturally in English, roses and tulips grow more slowly

This is a general statement about those kinds of flowers, not necessarily one specific rose and one specific tulip.

Using plurals would also be possible in some contexts:

• розы и тюльпаны растут медленнее

But the singular version sounds like a general observation about the two plant types as categories.

Because the subject is compound:

• роза и тюльпан = rose and tulip

Even though each noun is singular, together they form a plural subject, so the verb must be plural:

• роза и тюльпан растут
• мама и папа пришли
• кошка и собака спят

So растут is plural because there are two subject nouns joined by и.

Медленнее means more slowly or slower.

It is the comparative form of медленно (slowly), and in Russian comparatives often do not need an explicit than phrase if the comparison is understood from context.

So here:

• растут медленнее = grow more slowly

The implied comparison is something like:

• more slowly than with sunlight
• more slowly than they otherwise would

Here it functions adverbially, because it describes how they grow:

• растут как? → медленнее

So in English it is best understood as more slowly.

Russian comparative forms like быстрее, медленнее, лучше, хуже can often work in ways that look adjective-like or adverb-like depending on the sentence, but here the meaning is clearly adverbial.

Because Сколько ни поливай цветы is a subordinate concessive clause, and it is separated from the main clause by a comma.

Structure:

• Сколько ни polивай цветы, = subordinate clause
• без солнца роза и тюльпан растут медленнее. = main clause

In English, this is similar to:

• No matter how much you water the flowers, without sun a rose and a tulip grow more slowly.

Russian normally separates that first clause with a comma.

Yes, Russian word order is flexible, though the emphasis changes.

Original:

• Сколько ни поливай цветы, без солнца роза и тюльпан растут медленнее.

Possible variation:

• Без солнца роза и тюльпан растут медленнее, сколько ни поливай цветы.

This still means roughly the same thing, but the original order is more natural if you want to start with the concessive idea no matter how much you water them.

Russian word order often reflects emphasis and information flow more than strict grammatical necessity.

Yes. In English, both can work depending on context.

Russian сколько ни поливай can suggest:

• no matter how much you water
• no matter how often you water

The Russian wording does not sharply force one or the other here. It expresses repeated watering to whatever extent. English may choose the version that sounds most natural in context.

Most naturally, it sounds like a general truth.

• цветы = flowers in general
• роза и тюльпан = rose and tulip as plant types

So the sentence reads like a general statement about plant growth:

• watering cannot fully compensate for lack of sunlight

Depending on context, it could refer to actual flowers someone is caring for, but grammatically it sounds broad and general.