We plant our asparagus from crowns, in the Spring. The crowns are lifted in late March, from the fertile Polder beds in Holland, where in one year crowns will develop to 100 grammes in weight with roots extending to 1 foot long. We keep these crowns at +3° C before, either planting them, or despatching to our mail order customers.
We advise planting 4 crowns per square yard, or if in rows, 10” apart with rows 2 feet apart. This allows ridges to be built up over the crown, the soil both supporting fern growth and encouraging the production of firm and fatter spears.
Planting in the spring, with good quality, recently lifted crowns, will ensure that every single crown will develop in your bed to give 10 years of cutting. The quality of the crown is guaranteed and the job of growing is already half done.
Asparagus Plant Varieties
We have grown many varieties, two of which were disastrous, so we now resist the move to new ones until they are well tested. The two, both good for green production, that we recommend this year are:
“Gijnlim”, a Dutch hybrid that we originally planted in 1998, a great variety, thickish spears, good production and will be around for many more years yet.
“Guelph Millenium”, a variety developed much more recently in Guelph, Ontario which we are very pleased with and which we now offer. This variety will stand the cold better, is as good in quality as Gijnlim with better production in June, when the Dutch hybrids are running out of steam.
Asparagus plants do not like to sit in water all winter. If your soil is very heavy, consider building or creating a raised bed. Add sharp sand in all cases to aid drainage. Add organic manure. Now is your best chance to ensure maximum production from natural nutrients. If on free draining soil, chalks, sands or limestone, then adding organic material, manure or green waste will help retain moisture in the summer and will feed your crop.
In all cases ensure that the soil is not acid. Using a pH meter if in doubt, add calcium where necessary to achieve a level of 6.5. More than 7.2 or below 5.8 will reduce production and correcting later on is a problem.
Most spring planted beds will not require watering. Post cutting, ie from mid June, is the critical time for asparagus production. Clean, moist, supported, beds will produce healthy fern which is the power house for the following year’s production.