The history of agriculture, upon which the profession of gardening is predicated, is a tale as old as civilization itself. Yet, even as we have progressed from pastoral societies to industrial and information-based economies, the fundamental role of the gardener remains entrenched. However, the future landscape of the gardening industry is set to transform dramatically, driven by a host of socio-economic, technological, and environmental variables. This discourse seeks to illuminate these factors, prognosticate their impact, and examine the trends they are engendering, thereby offering a projection of the future of gardeners in.

Let's commence with an examination of the socio-economic variables. With urbanization forecasts predicting that by 2050, nearly 70% of the global population will reside in cities, the need for green spaces within these concrete jungles is surging. This urbanization trend is catalyzing a rising demand for urban gardeners, who are adept at leveraging limited space and resources to create verdant oases. This sector's exponential potential is further amplified when one considers the psychological benefits of gardening, elucidated by studies in environmental psychology. They highlight gardening's ability to attenuate stress, enhance mental well-being and promote physical health. This underscores the sociological value of gardeners in the urbanization narrative.

Next, the rise of technology in gardening is undeniable, and its footprint will only expand. Robotics and automation are revolutionizing the industry, with Robo-mowers and self-watering systems becoming commonplace. Dynamic AI-based gardening apps provide personalized care instructions for various plant species, while the adoption of IoT in gardening reduces water and resource consumption. Yet, this technological crescendo does not negate the necessity of human gardeners. Rather it redefines their role, necessitating the acquisition of new technical skills to operate, maintain, and troubleshoot these technologies.

Further, the burgeoning field of vertical and hydroponic gardening, enabled by advancements in LED and hydroponic technologies, offers lucrative avenues to gardeners. These methods, which facilitate indoor gardening and yield higher crop productivity, will continue to gain traction, especially in urban environments with spatial constraints. Comprehending these techniques and technologies will thus be integral to the gardener's toolkit in the future.

Looking at the environmental spectrum, climate change represents both a challenge and opportunity for gardeners. On one hand, unpredictable weather patterns and increasing temperatures threaten plant health and productivity. Conversely, these changes necessitate adaptive gardening practices, such as xeriscaping and the cultivation of climate-resilient flora. Additionally, the green rhetoric and rising environmental consciousness among consumers is driving demand for organic and sustainable gardening. These trends underscore the need for gardeners to stay on the cutting edge of environmental science and sustainable practices.

Lastly, the role of policy can't be disregarded. With governments around the world implementing green initiatives, gardeners can expect incentives and support for environmentally-friendly practices. However, they may also face heightened regulation, particularly when it comes to the use of chemical fertilizers and pesticides.

To extrapolate, the future of gardeners lies at the confluence of these socio-economic, technological, environmental, and policy trends. Their role will morph from traditional garden caretakers to green space architects, tech-savvy operators, sustainability advocates, and climate change warriors. This multidimensional role will require a diversified skill set, encompassing everything from botany and environmental science to technology and legislation.

In conclusion, while predicting the future is an exercise fraught with uncertainty, the analysis of these trends allows us to make informed conjectures about the future of gardeners in. Barring any drastic disruptions, we can anticipate a future where gardeners play a central role in shaping our urban landscapes, contributing to our environmental efforts, and enhancing our well-being. The profession will undoubtedly require continuous learning and adaptation, but the rewards - both tangible and intangible - are sure to be commensurate.