Grafting has begun …

We’ve started grafting some of the 200+ trees for the 63rd Street Farm orchard, to be located on the City of Boulder’s Andrus open space property just across the road from 63rd Street Farm. We planted out 50 Antonovka rootstocks at the farm last year in a nursery bed, and a few stray M-111s at home, and are starting to dig them up and bench graft them. First up: Golden Russet.

Heeled-in apple bench grafts in the shade of the north side of the house.

After grafting, our trees are ‘heeled in’ and covered with most sand or soil, in the shade of the north side of a building, to await healing over of the graft junction between scion and rootstock. It’s still early to be grafting, and we will probably need to protect these trees from freezes. Apple grafts heal well at 40-50 F, but severe cold would likely ruin them.


There are symptoms of an early spring out there (70°F today), and buds on some of the scion wood cut from around town are starting to swell. Not to say we won’t still have some tough winter conditions, but it’s better to graft, heel in, and protect the small trees than it is to try and graft with scionwood that is emerging from dormancy.

New orchard at 63rd Street Farm, plotted and holes dug

The new orchard going in on the Andrus property, owned by the City of Boulder and managed by Open Space and Mountain Parks (OSMP), for 63rd Street Farm is well underway.  Working with 63rd Street Farm, we developed the orchard plan over the past 9 months and have reach two major milestones.  First, the orchard blocks were measured and plotted, using several different colored flags to outline the blocks and locate individual trees, by rootstock and wild/domesticated varieties.  Second, the holes were dug/bored.  The OSMP agriculture team was kept in the loop, ok’d all of the plans as well as provided a work team with bobcat to bore the holes.  The team was composed of the bobcat and operator and a work crew from the Boulder County Sheriff’s Office.  Thanks to both organizations, OSMP and Sheriff’s Office for boring the orchard tree holes.  This happened about a month ago, giving plenty of freeze/thaw cycles to work on the sides and bottom of the holes before the trees are planted in a few months.  This process, the freeze/thaw cycle, is important for this type of soil when holes are bored instead of hand dug.  The boring compacts the clay in the soil on the bottom and the sides.  If the bottom and sides are not broken up prior to planting, the hole tends to form a clay pot, constraining the tree roots and severely compromising the long term health and productivity of the tree.  Had we bored the holes in the spring, immediately prior to planting, we would have had to manually break up the bottom and sides of the holes.

The OSMP/BCSO team bore trees holes on the Andrus Property in late January 2016

The OSMP/BCSO team bore trees holes on the Andrus Property in late January 2016, they are nearly finished, working on the last of the holes in the western block of trees.  Photo is looking NNW

The western block of the Andrus Property, where the wild apple trees will be planted

The western block of the Andrus Property, where the wild apple trees will be planted.  Photo is looking close to due south

 

The orchard as planned will be 231 trees, with a mix of dwarf, semi-dwarf and full sized rootstock, and a wide mix of wild, dessert and multi-purpose apple varieties.  First to fruit will be the dwarf trees, which will be taken out as they are shaded by the full sized trees, in 10 to 15 years.

Next big step, grafting…