The Coloma moated castle with a domain of approx. 15 ha is located right next to the village centre of Sint-Pieters-Leeuw and on the edge of the Zuun Valley nature reserve. The site forms a beautiful green lung 10 km southwest of Brussels. The Agency for Nature and Forests created a rose garden here in several phases from 1995 onwards. The rose collection is now scattered over the domain, but remains mainly concentrated on the enclosed west side. The rose garden is the central and unique asset of the Coloma domain. Because of a large collection of unique and/or old varieties, this rose collection is nationally and internationally renowned.

The domain is also home to a restored castle orchard with a collection of old fruit tree varieties, and the park has a number of exceptional trees. The Coloma domain is a starting point and resting point for many walks and bike rides through the Pajottenland. The park and the collection are open to the public and free of charge. 

The Coloma Castle was established as an architectural heritage. It was built in 1515 as a moated castle in a woody park. The moat was fed by a branch of the river Zuun. Later, a coach house was added to the estate, the current tavern, and later a garden pavilion with a staircase tower was built. 

The castle and soon also the de Viron manor will house several departments of the municipal administration. The domain is owned and managed by the Agency for Nature and Forests. The Agency wants to develop a new and ambitious vision for the future of the domain in dialogue with all stakeholders (among others the municipal administration, Tourism Flanders, rose associations and professionals).  This new interpretation, on the theme of the rose and Coloma’s rose collection, should focus on the different social needs, the exploitation and the experience of the domain. On the basis of this vision of the future, the Agency wants to commemorate the institution of the rose collection and give this historic site a new, sustainable life. The domain is looking for fresh ideas for a transformation and rejuvenation in which the rose collection will be reorganized. The domain can offer added value on many levels for a diverse public of tourists, for the inhabitants of Sint-Pieters-Leeuw and for the international rose lover or expert, and can become more attractive for young and old. The place should become hospitable, child-friendly and inclusive. 

Specific assets for the site are :

• Sint-Pieters-Leeuw is very much appreciated by tourists and recreational users, thanks to the beautiful landscape of the Pajottenland and numerous places of interest, both locally and in the surrounding area: in addition to the Coloma Domain, the Zuun Valley nature reserve, various other castles and nature reserves such as the Gaasbeek castle domain and the Groenenberg castle domain, and various breweries.
• The Coloma domain is located in the green outskirts of Brussels.
• The Coloma Rose Garden is one of the largest rose gardens in Europe. All the important ancestors of the modern rose were planted here, along with a complete collection of Lens roses. The whole offers opportunities for research, conservation of (genetic material of) species and education.

The aim of the master plan is to develop a unique vision for the future, in which the existing and new buildings, rose garden, park and landscape – with respect for the past and in line with the spatial policy vision of Sint-Pieters-Leeuw – form a coherent whole. The Agency wants a new and attractive story for the rose garden, with the rose at its centre, and with a focus on the experience throughout the seasons and for all visitors. The scenography and exploitation of the rose collection and its surroundings are part of the master plan. The new concept must be able to support the following management ambitions: sustainable management methods (water management, healthy soil, organic cycles, weed control, management costs, etc.), collection management (with the possible selection of rose varieties or themes), increased biodiversity and natural pest control, temporary or permanent pavilions.

The wider programme to be developed for the domain must be attractive and balanced, with attention paid to the organization of temporary or permanent activities or events. The park must allow and support creativity, insofar as it is linked to the intrinsic qualities and characteristics of the site. With the master plan, the Agency also wants to embed the domain in a broader context of current or to-be-developed area qualities and facilities on a broader scale. The new development offers opportunities for the upgrading and/or restoration of the landscape structures. Complementarity with similar sites in the green outskirts around Brussels is a point of attention. Considering connections with tourist routes or bicycle highways is also part of this. Effective multimodal accessibility is requested, at the local level and at the level of the Green Belt and the wider surroundings, and with links to existing tourist routes or networks. Practical requirements such as parking facilities, especially around the de Viron manor, where a library, municipal offices and services and meeting rooms will be located, are also part of the design assignment.

As an elaboration of the master plan, a layout plan is requested for a reception site. The reception should at least include the following functions: covered (outdoor) space for individual visitors, space for organized (outdoor) activities for 200 people (small markets, trainings and demonstrations, events, etc.), presence of water, electricity and sanitary facilities in a closable area.
The history, the heritage value, the specific landscape and the touristic and recreational aspects offer many opportunities as a context for an art commission. The master plan can therefore optionally provide space for commissioned art. Art is not seen in this regard as an instrument to help meet the social, touristic needs of the landscape, but can help question the context, add meaning, stimulate the imagination, in short, let the commissioning authority and the public experience the place with all their senses.

Selection criteria 

1. the general design-based expertise with regard to the project assignment
2. professional competence
3. the relevant experience

Award criteria 

1. the quality of the concept and vision development and of the design research, tested against the ambitions and expectations of the commissioning authority as formulated in the specifications: 
   1.1.  in a broad social context
   1.2.  applied more functionally to the requirements of the user
2. process-orientation and process-readiness
3. the composition and expertise of the design team
4. the approach to sustainability
5. fee

The weighting of the respective criteria has been determined as follows: 4 / 4 / 3 / 2 / 1. The weight of the sub-criteria is 1.