Tanaman mentimun (Cucumis sativus L.) merupakan salah satu jenis tanaman yang banyak di butuhkan pada masyarakat sehingga perlu ditingkatkan cara budidaya nya, dalam buah mentimun terdapat kandungan gizi yang sangat melimpah. Tingkat produktivitas mentimun di Kota Tarakan hingga tahun 2020 tergolong rendah yaitu sebesar 39,416 kuintal. Peningkatan pertumbuhan dan produski mentimun dapat dilakukan dengan pemanfaatan mulsa alang-alang dengan waktu pemberian yang berbeda. Penelitian ini menggunakan Rancangan Acak Kelompok (RAK) dengan satu faktor yaitu : M0 = kontrol(tanpa mulsa), M1 = pemasangan mulsa saat tanam bersamaan, M2 = pemasangan mulsa 1 MST dan M3 = pemasangan mulsa 2 MST. Parameter yang di amati meliputi : Tinggi tanaman, Diameter batang, Jumlah daun, Jumlah buah, Panjang buah, Diameter buah dan Berat buah. Data dianalisis dengan sidik ragam dan di uji lanjut menggunakan DMRT. Berdasarkan hasil penelitian waktu pemasangan mulsa saat tanam bersamaan (M1) berpengaruh nyata terhadap peningkatan tinggi tanaman 2 MST (8,25 cm), 3 MST (74,39 cm) dan 4 MST (112,37 cm). Peningkatan diameter batang diameter batang 2 MST (0,38 mm), 3 MST (0,68 mm) dan 4 MST (0,88 mm). Peningkatan jumlah daun 2 MST (4,00 helai), 3 MST (11,54 helai) dan 4 MST (17,83 helai). Pertambahan jumlah buah sebanyak 4,58. Peningkatan panjang buah sebanyak 28,88 cm. Peningkatan diameter buah sebesar 4,69 cm dan Peningkatan bobot buah sebesar 471,68 gram.

Kata Kunci: Waktu Pemasangan Mulsa, Pertumbuhan Dan Produksi, Organik Dan Nonorganik, Mentimun

Cucumber plants (Cucumis sativus L.) are one of the types of plants that are widely needed in the community, thus it needs to be improved in its cultivation methods because in cucumber fruits, there is a very abundant nutritional content. The productivity level of cucumbers in Tarakan City until 2020 was relatively low, which was 39,416 quintals. Increasing the growth and yield of cucumbers can be done by utilizing reed mulch with different application times. This study used a Group Random Design (RAK) with one factor, namely: MO control (without mulch), M1 mulch when planting at the same time, M2 = mulch 1 MST and M3 mulch 2 MST. The parameters observed include: Plant height, Stem diameter, Number of leaves, Number of fruits, Fruit length, diameter and weight. The data was analyzed with various fingerprints and further tested using DMRT. Based on the results of study, the time of mulching during simultaneous planting (M1) had a real effect on the increase in plant height of 2 MST (8.25 cm), 3 MST (74.39 cm) and 4 MST (112.37 cm). The increase in rod diameter was 2 MST (0.38 mm), 3 MST (0.68 mm) and 4 MST (0.88 mm). An increase in the number of leaves was 2 MST (4.00 leaves), 3 MST (11.54 leaves) and 4 MST (17.83 leaves). The increase in the number of fruits was 4.58, and the increased fruit length was 28.88 cm. An increase in fruit diameter was 4.69 cm and an increase in fruit weight was 471.68 grams. Keywords: Mulching Time, Organic and Nonorganic Growth and Production, Cucumber