Seamless Flower Dress has an unconventional construction: the front and back start from the centre of the flower, and are initially worked separately - you join the two pieces by knitting the top down raglan sleeves onto them. The skirt is worked after sleeves, top down and in the round. The neck is finished with I-cord bind off, with a button and a loop at the back.
The skirt is wider for baby sizes up to 2 years to accommodate a nappy/ round tummy. The increase rate is lower for sizes 3-4 to 7-8 years (shown in size 3-4 years).

The pattern contains detailed instructions, with photos, for crochet cast on used to start the flower, finishing neck with I cord bind off, and making a buttonhole loop.

The pattern consist of 3 pdf files:
sizes 0-3 to 6-12 months,
sizes 1-1.5 and 1.5-2 years,
sizes 3-4, 5-6 and 7-8 years.
(You will be able to download all three.)

Skill level: intermediate / experienced
You need to be able to knit in the round on dp and circular needles, work short rows, increases, decreases, and use provisional and backward loop cast on methods.

Sizes: 0-3, 3-6, 6-12 months; 1-1.5, 1.5-2, 3-4, 5-6, 7-8 years

Gauge:
22 sts and 30 rows to 10 cm/ 4’’ in stockinette st

Finished chest measurements:
46, 50, 53, 56, 60, 64, 68, 72 cm
18, 19.5, 21, 22, 23.5, 25, 26.5, 28 in

Yarn:
DK weight yarn:
300, 400, 450, 450, 500, 550, 800, 950 metres
330, 440, 500, 500, 550, 610, 880, 1040 yards
(shown in Wendy 100% Cotton DK).

You will also need:
4 mm circular needles: 40, 60, 80 and 100 cm long (depending on size)
a set of 4 mm dp needles
a set of 3.5 mm dp needles (for sleeve rib)
one larger size needle, 4.5 or 5 mm
st markers
scrap yarn for provisional cast on
1 small button, about 12-15 mm diameter
crochet hook size as needles or smaller, and a pen/pencil, about 8-10 mm across (for casting on)
yarn needle to make a button loop, and a smaller needle to sew a button on

You might need to use different size needles to obtain the required gauge. Take time to make a gauge swatch, as incorrect gauge could result in the dress being too small or too large. Adjust needle size, if necessary.

A t-shirt version and a baby hat pattern are also available:
Seamless Flower T-shirt
Baby Flower Hat (free pattern)