春天来到伦敦

Good word picking, such as 好"像,"  where there seems to be more and more native Chinese speakers choose the incorrect character.

春天来到伦敦了

鳴 not 明

花 not 话

There are many ways to correct or express your sentiment.  It is best to provide an English version so that we can help you better.

春天来到伦敦

Now that you have your English version, it is much easier to convey your intent and nuance :)

 "It seems as though yesterday spring finally arrived in London. 春天似乎昨日来至伦敦了 I used 昨日 instead of 昨天 is just like in English, repeating the same major word makes the sentence boring.  終於, 最后 = finally. 似乎 = as if.  Intent totally different.  来至 is a bit more formal and poetic than the colloquial 到.  It is better for writing than is to speak.  At the same time, the tone of your English is quite poetic too :)

Songbirds are singing in my garden, 园中啼鳥在歌唱 Actually, this translates into "chirping birds in my garden are singng".  To do a literal translation is not possible since Chinese don't have "歌鳥" songbird.  In writing, pronoun omissions are defaulted to the writer unless there is confusion. 

tiny blue flowers are opening, 小花遍地藍 Again this is a cultural bias in expressing elegance.  English tends to be direct while Chinese tends to go indirect.  Hence, doing a straight translation usually gives away the writer's background.  Here translating literally back from Chinese becomes, "tiny flowers blue all over the ground".  Here's another example, 東日初起 if translated directly into English, "The eastern sun just rose" would not be good, since in English, it is redundant to use "east" since it is a fact that the sun rises in the east!  It would be better to write as "The morning sun just rose/came up".  If you are serious in learning any language, my suggestion is also to read up on the culture and biases.  This is how I learn my Chinese.

the sun is shining, Sharon's version of 阳光普照大地，is closer to your words but she still added, 大地 (the great earth/land) due to grammar rules 普照 = shines. So an object is needed.  There is no gerund in Chinese.  Violet's use is of a standard expression to mean the same thing in English.  As for my earlier version, it is a bit off since mine conveys "shining brightly".  Now with your English, it would be better to use "滿地陽光" but 地 was used in the previous line, so this is not good either.    風和日丽 would be too much in my opinion.So, violet's version is the best in keeping the tone of your sentences.

everyone is happy."  大家很高兴 This is the simplest way to express :)

Hope these explanations help you in understanding how to write better :)

好像春天昨天最后达到伦敦。我的花园里面小鸟明着，微小蓝色的话开着，天阳光着，大家都愉快了。