This year, for the first time ever, I left my parsnip beds as they were without emptying them out to make the boring easier. I was therefore anticipating some problems and an almighty struggle to push the six foot 6 inches long steel bar down to a minimum of 5 foot 6 inches in depth. The onions are doing particularly well this year and I have now potted them up into their final pots from where they will be planted out in their beds which have now been completed.
My parsnips, the variety Gladiator, were sown slightly later than I had anticipated on Wednesday the 21st of February and the whole operation went exceptionally well. This year, for the first time ever, I left my beds as they were without emptying them out to make the boring easier. I was therefore anticipating some problems and an almighty struggle to push the six foot 6 inches long steel bar down to a minimum of 5 foot 6 inches in depth.
My original idea was to use a 4 inch diameter plastic pipe to core out the sand to a depth of about 2 feet and thereafter using a 3 inch pipe to go down further and completing the job by driving down the steel bar as far as it would go.
Whilst boring the holes the bar would also be moved around within the hole in order to from a conical shape. However after a chat with Jim Thompson, a fellow exhibitor of collections, he stated that when he had tried the same method he found out to his dismay that he was unable to get rid of the ledge that was inevitably left at the end of the 4 inch bore hole and some of his parsnips were mis-shapen. As a result of this I didn’t use the 4 inch pipe but bored down to 3 foot six with the 3 inch plastic pipe. This took about three goes to get down to that depth and the holes were duly completed with the bar to finish off with a well formed conical hole that were a minimum of 5 ft 6 inches and 5 inches in diameter across the top.
Reduction in number of specimens
Another change to plan was a reduction in the number of specimens per bed, each bed is 5.75 feet long and 2 foot wide giving me a surface are of 11.5 square feet and last year I had 16 bore holes in each bed which means that each parsnip had 0.72 square foot of surface area to develop in. It dawned on me when thinking about sowing space what was the comparison between my beds and a 45 gallon drum which has a diameter of 23 inches giving a surface area of nearly 2.88 square feet. With four stations of parsnips usually allowed per drum, this means that every parsnip has 0.72 square foot to develop to it”s optimum size, exactly the same surface area as my beds.
Having thought the whole process through I came to the conclusion that as my parsnips were not seemingly achieving good size, the quantity per bed must have been too much. This time I have reduced the quantity by half, I now have only bored eight holes per bed so with four beds in total I hope to have 32 parsnips with each one having 1.44 square feet of surface area to grow in. I just hope that this sort of distance will produce much larger specimens than previously.
The following week I went down to Jim’s garden where I have 6 forty five gallon drums filled with fresh sand on top of a deep trench of sand which allows me to bore holes to the same depth as at home. This year I have reduced the quantity per drum from four to three, again giving a larger surface area for each parsnip to develop in.
The variety that I sowed was again Gladiator in five drums whilst the last one had a new F1 hybrid variety called Excalibur which I am trialling
This means that I have a total of 50 parsnips growing, quite honestly if I can not get six top quality parsnips from 50 bore holes, I am unlikely to get them if I struggled with 150 bore holes, there would have to be something wrong with some aspect of the growing. I will certainly keep you informed on how they perform.
The onions are doing particularly well this year and I have now potted them up into their final pots from where they will be planted out in their beds which have now been completed.
The next job is to lay down the heating cables so that I can raise the soil temperature to a minimum of 60F at planting out time which will be towards the end of the month when the beds have warmed up. Laying the cable is an awkward job and is best done if you can have someone to give you a hand to keep the cable flat on the bottom of the trench while you cover it over with soil.
My cable is laid at between 6 and 8 inches deep and below the level of the root ball when planted. If you haven’t got the facilities for warming up your soil with cables then the best method is to properly prepare the bed then cover it over completely with some clear polythene. This is far superior to black polythene as the heat is passed right through it to the soil whilst the black polythene retains it on the surface. Another added benefit of using clear polythene is that as the soil warms up underneath, so the weeds begin to germinate and when the soil has reached 60F or at least 55F, you can remove the clear polythene, weed the bed clean and then replace with black and white polythene.
The reason for warming up the soil is obvious, it gets the plants off to a flying start from which they never look back, there’s nothing worst than looking at a bed of onions that have clearly had a check to their growth and will inevitably give you problems later on. I don’t really consider that the air temperature is half as important as the soil temperature, if the roots are planted in soil from which they can grow away, the temperature that the foliage is subjected to is not that crucial and will not have a detrimental effect on the onions.
Do not try and lay the black and white polythene immediately on top of the soil when the temperature is 50F, the very fact that the white surface is uppermost will reflect light and heat away from it and thereby cause your soil temperature to drop as much as 5 degrees which can have a significant effect on the onions. Lifting the initial temperature to 60F and then placing on the black and white polythene will reduce the temperature to 55F but still adequate for planting under. If you are unable to achieve any of the above then it’s far better to pot your onions up into larger pots and plant them at a later date when soil temperatures will be naturally higher.