David Hockney: A Bigger Picture, Royal Academy

These are, we are told, David Hockney's landscape works, and in that they depict the outdoors - early Grand Canyons and LA scenes, Yorkshire from the Nineties to now - that is correct. As a description, however, it comes nowhere near encapsulating the mystical, profound, plain beautiful pictures presented at the Royal Academy.

The first paintings you encounter are both announcements of intention and tentative conclusions. These are seasonal versions of Three Trees Near Thixendale (2007-8), each nearly two metres by five, across eight canvases, capturing with elegant swoops bare purple-black branches in winter and the hesitant luxuriance of spring, summer's bursting fullness and autumnal decline. Spring has the sky of an Old Master even as thin, brief Post-Impressionist brushstrokes summon the fields.

These paintings, separately and together, give the most beautiful voice to Hockney's concern with the passing of time

Hockney is working in whichever mode takes his fancy because he can, and this is demonstrated time and again through the show: whether he is using an iPad for instant en plein air action or painting in oils from memory, as here, he never loses command. These pictures, whose age-old theme is refreshed by their beauty, have the consideration of a lifetime's painting and the energy for more. They, having gestated and evolved in his head, attaining mythical quality, predict the vibrancy of the new work even as they indicate Hockney's peaceful acceptance of a world beyond himself.

Hurly-burly, aggression and panic are all but banished from the new work. A Closer Grand Canyon (1998) across its 60 panels feels anxious, only a narrow strip given to blue sky, its brushstrokes still slightly rough, its perspective vertiginous. There is meditation in the new work, even amid gaudy Fauvist colouring. Several of the paintings in the Winter Timber and Totems room, such as the monumental Winter Timber (2009) across 15 canvases (pictured above), with its somewhat grouchy be-faced bright purple tree stump, ochre logs lying along the receding road, brown ferns and blue trees, have a radiating cultic stillness. The purple-shading-to-yellow tree stump in Still Standing (2009) is a masterpiece of tone, as delicate in its deadness as anything here.

As with the timber and tree stump, Hockney has tackled several scenes over and over and over again, a reaffirmation of the art of concentration best developed in Monet's Water Lilies. Particularly successful in this respect is the Woldgate Woods series (2006) (see main image). Painted from the same spot, Hockney has given them an audacious, challenging composition, with a confrontational tree almost pushing out of the foreground; it puts you into the picture, into Hockney's position, in an instant. There is then something very wonderful about the dotted foliage on the trees and on the floor, the inviting pale trunks and lithe shadows of the trees, the seasonal colourings and the path extending straight forward. These paintings, separately and together, give the most beautiful voice to Hockney's concern with the passing of time.

That includes the work made especially for the largest room in the Royal Academy, The Arrival of Spring in Woldgate, Easy Yorkshire in 2011 (twenty-eleven). 51 drawings, made on an iPad and then printed out on a bigger scale, capture different snapshots of Woldgate as spindly branches take on leaves and the sky lightens through countless shades of blue, and one immense painting, nearly 10 metres across, on 32 canvases, acts as supposed summation to them all.

Painted with a sure hand - there is no hesitation anywhere, in fact - it seduces you with its rich vision of spring, but is in fact less interesting than its companions, which show another medium Hockney has mastered. 2 January in this series (pictured left) shows the vivid colouration and the wide range of marks he can make on the iPad. The instant documents of the scene make the larger work almost too considered.

Conversely, the new video works, made by strapping nine cameras, three by three, to a Jeep and slowly moving down Woldgate Woods, are depictions of an instant but are probably themselves too artificial. Hockney is making the point that he has done throughout his career, by using both multiple canvases for paintings and arrhythmic photocollages, that the real world cannot be captured from one angle by a "flat" work of art, indeed that there is no 'real' world, only our particular perception - but it feels more like a technical experiment here. He is doing in 2011 what Picasso did a century ago, adding nothing.

For such bright and large works, for an artist obsessed with "bigger" and "closer", this is a remarkably quiet show. Hockney has mastered every type of painting he has turned his hand to, vied with his glorious predecessors and immersed himself in practically every leaf of his native landscape, once abandoned by him, now reclaimed. Yet Hockney, in his works here so persistently at war with the boundaries of painting, has no trouble turning this conflict into graceful, meditative works with a profound, almost moving love of place.

• David Hockney: A Bigger Picture is on at the Royal Academy until 9 April