Even if you don’t have a greenhouse, you can start you plants early. You just need a little planning.
Some crops can grow well with only a few hours of light a day. Lettuces, parsley, and many other leafy greens can easily be started inside. Fruiting plants like tomatoes do require more light. If the soil is cool and there isn’t enough light, tomatoes will ‘stretch’. This makes their stems weak.
Most crops can be easily grown in containers, but choosing the depth of the container is important. Lettuces, greens, chives, and mints are examples of crops that may be grown in shallow pots. Heavy feeders and large root crops such as: tomatoes, melons, squash, carrots, potatoes, and onions are examples of plants needing deeper containers. Even fruits like strawberries can be successfully grown in containers.
If setting out crops before the last frost, be prepared to protect them during the nights which temperatures drop. Frost cover clothes are easy to find almost anywhere plants are sold. Light weight scraps of fabric can also work. Be sure to to provide support of some kind for these coverings. Frost can weigh them down just enough to put pressure on young tender crops. Larger, more mature crops may not need the extra support.
Old soda bottles are great for mini greenhouses. Be sure caps are off during day time so your tender plants aren’t cooked and receive fresh air.
Here are a few videos on starting plants early…