Swedes - all greens and little root

[Number Six]

As usual, I planted my swedes from seed in the raised beds that had been used for onions and garlic (following a couple of weeks gap for fertiliser etc). I am now seeing vigorous growth in the leaves but the roots still look very small. Is there anything I should be doing to promote root growth? Grateful for any advice!
Regards
John

[Number Six]

[Jayb]

When were they sown Number Six and have they had a lot of fertilizer?

[Big Gee]

Too much nitrogen is the usual culprit. Lush leaves less root development.

It's still early days - they have a few months of growth to go yet, so they probably will bulk up a bit more for you over the winter. Did you sow them a bit late in the season?

To encourage root growth you need a feed with a higher phosphorus content (the 'P' in N-P-K ratios of synthetic fertilizers). If you think that too much nitrogen & not enough phosphorus is the problem look for a 3-20-20 ratio fertilizer. The 20-20 represents the phosphorus & potassium content.

I don't care much for synthetic fertilizers, if you grow organically try Rock Phosphate or even Bone Meal.

I hope that helps!

[Number Six]

Many thanks indeed for the replies. I did sow late in the season (probably late July) and, yes, I had applied synthetic fertiliser without being aware of N-P-K ratios. I shall definitely bear that in mind for next year. In the meantime, I presume that I should just let nature take its course - or would cutting back some of the greenery help?

[gray1720]

Just curious - I've never followed anything closely with swedes before. Do they not like it really hard underneath like brassicas, and especially caulis, generally?

I have amazing brassicas* this year, like I've never had before, and they're on a bit that was dug last autumn then stood underwater for several weeks in winter, so it was really rock solid when I started planting.

Adrian

* I know, I'm boasting

[Big Gee]

I believe the main reason for planting brassicas in firm soil is to prevent 'rocking'  it is disturbance to the root hairs that causes them to grow poorly. What brassicas (e.g. cabbage) need is copious amounts of Nitrogen to promote green leaf development - which is the part of the plant you harvest to eat. However in the case of swedes (although they are a member of the brassica family) what you harvest is the swollen root of the plant, so too much Nitrogen can promote too much leaf growth at the expense of root development.

[jimc]

I agree with you Big Gee with the fertilising. No.6's planting date of July puts them at about 2 months old so they should have plenty of time to grow yet so I am sure you will get a good harvest as time goes on.