By Stylus
United Kingdom 
Why are my trailing nasturtiums not trailing? I've planted 3 varieties of trailing nasturtiums - all of which grow long & trailing in my daughter's garden - but for 2 years running they've remained short & stumpy; they get to about 3-4 inches, with little fat stalks & a few flowers, & that's it. They are on a south-facing roof terrace in Brighton, & get lots of sun (when it's sunny).They're planted in baskets in old soil (not especially rich). Please see photo attached.
21 Jun, 2013
Answers
They do look pretty nitrogen deficient.
22 Jun, 2013
Thanks very much both. We put some 'Miracle Gro' on them when they were quite small; would this do? I can't see the ingredients written anywhere on the bottle to see if it contains nitrogen, though I assume so. They're actually starting to develop flowers, although they're all small & stumpy, with quite thick stems (much thicker than when they grow long & trailing).
23 Jun, 2013
Normal formula Miracle-Gro does have nitrogen in it--it shows up in the "guaranteed analysis" on the box. Here in the desert we use it every 2 weeks in containers, so one application doesn't last very long.
25 Jun, 2013
You may have touched on the answer. They probably want sun and a slightly richer start. Try a feed, just to get 'em a bit bigger and we'll all pray for more sun.
21 Jun, 2013