Indonesia is a tropical country which has two seasons, namely the rainy season and the dry season. Rainfall that occurs will vary in each area depending on the altitude of the area, climate, season, and other factors. Medan Selayang Subdistrict is the Subdistrict with the closest distance to the rain station. Where the closer the location of the study area to the rain station, the more accurate the rainfall data obtained will be. One way to make it easier to record and process data is to create a rainfall map by utilizing spatial analysis through a Geographic Information System (GIS). The data in this study are rainfall data and geographic coordinate data obtained from the Meteorology, Climatology and Geophysics Agency in the Medan City area. After data collection, data processing was carried out using the QGIS 3.10 application. with the Inverse Distance Weighted (IDW) interpolation method. From the results of processing rainfall maps in the Medan Selayang sub-district using Inverse Distance Weighted (IDW) interpolation, the rainfall values (rainfall) ranged from 3029.74 mm/year – 3164.20 mm/year.

Abstrak: Pupuk sangat diperlukan tanaman agar bisa tumbuh subur. Dibanding pupuk kimiawi, petani di Kelompok Tani Songgo Mulyo Kelurahan Sidomulyo, Kecamatan Stabat, Kabupaten Langkat lebih memilih pupuk kompos karena banyak keunggulan. Pupuk kompos karena berasal dari limbah organik sehingga aman untuk tanaman. Pupuk kompos juga relatif mudah pembuatannya. Kelompok Tani Songgo Mulyo mulai memproduksi pupuk kompos sejak tahun 2017. Karena memang fasilitas yang tersedia masih sangat terbatas sehingga mengurangi produktifitas pupuk kompos yang seharusnya bisa ditingkatkan. Dalam pengolahan sehari-hari, kelompok tani menggunakan bangunan sederhana dan untuk penjemuran menggunakan lantai tanah. Penjemuran bahan pupuk kompos pada lantai tanah tentu tidak efektif dalam mengurangi kadar air, terutama saat musim hujan. Solusi yang ditawarkan pada kegiatan ini berupa pembangunan lantai jemur sebagai tempat penjemuran bahan pupuk kompos di bawah sinar matahari untuk mengurangi kadar airnya. Pelaksanaan dimulai dengan pengukuran dan pemasangan bowplank, kemudian pembersihan dan perataan tanah/lahan, pemasangan pondasi batu kali keliling, pengurugan dan pemadatan tanah/lahan, pengurugan dengan pasir urug di atas lapisan tanah urug setebal 5 cm, pengecoran beton rabat 1pc : 3ps : 5kr, tebal 10 cm, dan finishing lantai dengan acian pc. Hasil dari pelaksanaan kegiatan ini adalah lantai jemur ukuran 5 x 10 m. Setelah kegiatan pengabdian, penjemuran limbah organik dilakukan pada lantai jemur yang telah dibangun dan hanya membutuhkan 1 hari saja untuk mendapatkan kekeringan yang diinginkan, dimana sebelum kegiatan, pengeringan membutuhkan waktu ± 2 hari.Abstract: Fertilizer is necessary for plants to thrive. Compared to chemical fertilizers, farmers in the Songgo Mulyo Farmer Group, Sidomulyo Village, Stabat District, Langkat Regency prefer compost because of its many advantages. Compost because it comes from organic waste so it is safe for plants. Compost is also relatively easy to make. The Songgo Mulyo Farmer's Group started producing compost since 2017. Because the available facilities are still very limited, thus reducing the productivity of compost which should be increased. In daily processing, farmer groups use simple buildings and for drying use earthen floors. Drying compost material on the ground floor is certainly not effective in reducing water content, especially during the rainy season. The solution offered in this activity is the construction of a drying floor as a place for drying compost material under the sun to reduce its water content. The implementation begins with measuring and installing the bow plank, then cleaning and leveling the soil/land, installing a stone foundation around the river, backfilling and compacting the soil/land, backfilling with backfill sand on top of a 5 cm thick layer of backfill, casting concrete rebates 1pc : 3ps : 5kr , 10 cm thick, and floor finishing with PC repair. The result of this activity is a drying floor measuring 5 x 10 m. After the devotion, drying of organic waste is carried out on the drying floor that has been built and only takes 1 day to get the desired dryness, where before the devotion, drying takes ± 2 days.