Question
I am getting ready to plant some leyland cypress.  What is the best fertilizer to help them get a good start?

Answer
I would go to home depot or lowes and pick up a bag of "Espoma Hollytone". This is an acidifying fertilizer for plants which like acidic conditions, such as hollies, azaleas, and layland cypress, etc.

Use it now but don't over fertilize. Use directions on the bag and apply about 1/2 the recommended amount. Especially in sandy soils, leyland cypress has shown signs of over fertilizing, and therefore it is better to split the application: once at time of planting and one about 60-90 days later. Try to fertilize the 2nd time at least 3 months before first frost. E.g. if you get frost in november, try not to fertilize after august 1st.

Make sure you water the fertilizer in well.

If you can not find holly-tone, you can also buy 14-7-7 slow release fertilizer (labled as azalea food). It is the same, but just not organic like Holly tone. Finally you can use miracid (from makers of miracle grow) although it is not slow release. I really prefer using slow release products when fertilizing Cypress.

When planting, it is a good idea to mix in a 2-3" layer of canadian peatmoss sphagnum (available in bales at garden centers and home improvement centers). It is naturally acidic and will loosen clay soils and retain moisture in sandy loam. Make sure you wet it thoroughly before incorproating into the planting hole.